98 results on '"H3Africa Consortium"'
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2. Genetic substructure and complex demographic history of South African Bantu speakers
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Dhriti Sengupta, Ananyo Choudhury, Cesar Fortes-Lima, Shaun Aron, Gavin Whitelaw, Koen Bostoen, Hilde Gunnink, Natalia Chousou-Polydouri, Peter Delius, Stephen Tollman, F. Xavier Gómez-Olivé, Shane Norris, Felistas Mashinya, Marianne Alberts, AWI-Gen Study, H3Africa Consortium, Scott Hazelhurst, Carina M. Schlebusch, and Michèle Ramsay
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Science - Abstract
Despite linguistic and geographic diversity in South Eastern Bantu-speaking (SEB) groups of South Africa, genetic variation in these groups has not been investigated in depth. Here, the authors analyse genome-wide data from 5056 individuals, providing insights into demographic history across SEB groups.
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- 2021
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3. Author Correction: Meta-analysis of sub-Saharan African studies provides insights into genetic architecture of lipid traits
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Ananyo Choudhury, Jean-Tristan Brandenburg, Tinashe Chikowore, Dhriti Sengupta, Palwende Romuald Boua, Nigel J. Crowther, Godfred Agongo, Gershim Asiki, F. Xavier Gómez-Olivé, Isaac Kisiangani, Eric Maimela, Matshane Masemola-Maphutha, Lisa K. Micklesfield, Engelbert A. Nonterah, Shane A. Norris, Hermann Sorgho, Halidou Tinto, Stephen Tollman, Sarah E. Graham, Cristen J. Willer, AWI-Gen study, H3Africa Consortium, Scott Hazelhurst, and Michèle Ramsay
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Science - Published
- 2022
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4. Impact of environmental factors on Biomphalaria pfeifferi vector capacity leading to human infection by Schistosoma mansoni in two regions of western Côte d'Ivoire
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Edwige A. Sokouri, Bernardin Ahouty Ahouty, Martial N’Djetchi, Innocent A. Abé, Ble Gbacla Flora Dominique Yao, Thomas Konan Konan, Annette MacLeod, Harry Noyes, Oscar Nyangiri, Enock Matovu, Mathurin Koffi, and the TrypanoGEN+ Research Group of the H3Africa Consortium
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Environmental factors ,Biomphalaria pfeifferi ,Schistosoma mansoni ,Thermophilic coliforms ,Western Côte d’Ivoire ,Infectious and parasitic diseases ,RC109-216 - Abstract
A bstract Background Intestinal schistosomiasis remains a worrying health problem, particularly in western Côte d'Ivoire, despite control efforts. It is therefore necessary to understand all the factors involved in the development of the disease, including biotic and abiotic factors. The aim of this study was to examine the factors that could support the maintenance of the intermediate host and its vectorial capacity in western Côte d'Ivoire. Methods Data on river physicochemical, microbiological, and climatic parameters, the presence or absence of snails with Schistosoma mansoni, and human infections were collected between January 2020 and February 2021. Spearman rank correlation tests, Mann–Whitney, analysis of variance (ANOVA), and an appropriate model selection procedure were used to analyze the data. Results The overall prevalence of infected snails was 56.05%, with infection reaching 100% in some collection sites and localities. Of 26 sites examined, 25 contained thermophilic coliforms and 22 contained Escherichia coli. Biomphalaria pfeifferi was observed in environments with lower land surface temperature (LST) and higher relative air humidity (RAH), and B. pfeifferi infection predominated in more acidic environments. Thermal coliforms and E. coli preferred higher pH levels. Lower maximum LST (LST_Max) and higher RAH and minimum LST (LST_Min) were favorable to E. coli, and lower LST_Max favored coliforms. The presence of B. pfeifferi was positively influenced by water temperature (T °C), LST_Min, RAH, and precipitation (Pp) (P
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- 2024
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5. A novel de novo variant in the RUNX2 gene causes cleidocranial dysplasia in a Malian girl
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Lassana Cissé, Abdoulaye Yalcouyé, Kadidia Oumar Touré, Youlouza Coulibaly, Alassane Baneye Maiga, Salia Bamba, Dramane Diallo, Salimata Diarra, Abdoulaye Taméga, Oumou Traoré, Mahamadou Kotioumbé, Moussa Aly Sangaré, Hamidou Oumar Ba, Assiatou Simaga, Fatogoma Issa Koné, Oumar Samassekou, Amadou Koné, Cheick Oumar Guinto, Guida Landouré, and the H3Africa consortium
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cleidocranial dysplasia ,de novo genetic variant ,Mali ,RUNX2 ,West Africa ,Medicine ,Medicine (General) ,R5-920 - Abstract
Key Clinical Message Cleidocranial dysplasia (CCD) is a rare genetic skeletal disorder with only few cases reported in Africa, mostly based on clinical and radiological findings. We report the first case in Mali, caused by a novel de novo variant in the RUNX2 gene. Abstract Cleidocranial dysplasia (CCD) is a rare autosomal dominant skeletal dysplasia characterized by an aplastic/hypoplastic clavicles, patent sutures and fontanels, dental abnormalities and a variety of other skeletal changes. We report a novel de novo variant in the RUNX2 gene causing a severe phenotype of CCD in a Malian girl.
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- 2024
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6. Incorporating CNV analysis improves the yield of exome sequencing for rare monogenic disorders—an important consideration for resource-constrained settings
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Nadja Louw, Nadia Carstens, Zané Lombard, and for DDD-Africa as members of the H3Africa Consortium
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copy number variation ,exome sequencing ,low-middle-income countries ,variant calling ,rare disease ,monogenic disorders ,Genetics ,QH426-470 - Abstract
Exome sequencing (ES) is a recommended first-tier diagnostic test for many rare monogenic diseases. It allows for the detection of both single-nucleotide variants (SNVs) and copy number variants (CNVs) in coding exonic regions of the genome in a single test, and this dual analysis is a valuable approach, especially in limited resource settings. Single-nucleotide variants are well studied; however, the incorporation of copy number variant analysis tools into variant calling pipelines has not been implemented yet as a routine diagnostic test, and chromosomal microarray is still more widely used to detect copy number variants. Research shows that combined single and copy number variant analysis can lead to a diagnostic yield of up to 58%, increasing the yield with as much as 18% from the single-nucleotide variant only pipeline. Importantly, this is achieved with the consideration of computational costs only, without incurring any additional sequencing costs. This mini review provides an overview of copy number variant analysis from exome data and what the current recommendations are for this type of analysis. We also present an overview on rare monogenic disease research standard practices in resource-limited settings. We present evidence that integrating copy number variant detection tools into a standard exome sequencing analysis pipeline improves diagnostic yield and should be considered a significantly beneficial addition, with relatively low-cost implications. Routine implementation in underrepresented populations and limited resource settings will promote generation and sharing of CNV datasets and provide momentum to build core centers for this niche within genomic medicine.
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- 2023
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7. Differences in gene expression profiles in early and late stage rhodesiense HAT individuals in Malawi.
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Peter Nambala, Julius Mulindwa, Harry Noyes, Vincent Pius Alibu, Barbara Nerima, Joyce Namulondo, Oscar Nyangiri, Enock Matovu, Annette MacLeod, Janelisa Musaya, and TrypanoGEN+ Research Group as Members of the H3Africa Consortium
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
T. b. rhodesiense is the causative agent of Rhodesian human African trypanosomiasis (r-HAT) in Malawi. Clinical presentation of r-HAT in Malawi varies between foci and differs from East African HAT clinical phenotypes. The purpose of this study was to gain more insights into the transcriptomic profiles of patients with early stage 1 and late stage 2 HAT disease in Malawi. Whole blood from individuals infected with T. b. rhodesiense was used for RNA-Seq. Control samples were from healthy trypanosome negative individuals matched on sex, age range, and disease foci. Illumina sequence FASTQ reads were aligned to the GRCh38 release 84 human genome sequence using HiSat2 and differential analysis was done in R Studio using the DESeq2 package. XGR, ExpressAnalyst and InnateDB algorithms were used for functional annotation and gene enrichment analysis of significant differentially expressed genes. RNA-seq was done on 23 r-HAT case samples and 28 healthy controls with 7 controls excluded for downstream analysis as outliers. A total of 4519 genes were significant differentially expressed (p adjusted
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- 2023
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8. Variants of IL6, IL10, FCN2, RNASE3, IL12B and IL17B loci are associated with Schistosoma mansoni worm burden in the Albert Nile region of Uganda.
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Oscar Asanya Nyangiri, Julius Mulindwa, Joyce Namulondo, Anna Kitibwa, Jacent Nassuuna, Alison Elliott, Magambo Phillip Kimuda, Alex Boobo, Barbara Nerima, Moses Adriko, Nathan J Dunton, Gaganjit Kaur Madhan, Mark Kristiansen, Miriam Casacuberta-Partal, Harry Noyes, Enock Matovu, and TrypanoGEN+ Research group of the H3Africa consortium
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
BackgroundIndividuals genetically susceptible to high schistosomiasis worm burden may contribute disproportionately to transmission and could be prioritized for control. Identifying genes involved may guide development of therapy.Methodology/principal findingsA cohort of 606 children aged 10-15 years were recruited in the Albert Nile region of Uganda and assessed for Schistosoma mansoni worm burden using the Up-Converting Particle Lateral Flow (UCP-LF) test detecting circulating anodic antigen (CAA), point-of-care Circulating Cathodic Antigen (POC-CCA) and Kato-Katz tests. Whole genome genotyping was conducted on 326 children comprising the top and bottom 25% of worm burden. Linear models were fitted to identify variants associated with worm burden in preselected candidate genes. Expression quantitative trait locus (eQTL) analysis was conducted for candidate genes with UCP-LF worm burden included as a covariate. Single Nucleotide Polymorphism loci associated with UCP-LF CAA included IL6 rs2066992 (OR = 0.43, p = 0.0006) and rs7793163 (OR = 2.0, p = 0.0007); IL21 SNP kgp513476 (OR 1.79, p = 0.0025) and IL17B SNP kgp708159 (OR = 0.35, p = 0.0028). A haplotype in the IL10 locus was associated with lower worm burden (OR = 0.53, p = 0.015) and overlapped SNPs rs1800896, rs1800871 and rs1800872. Significant haplotypes (pConclusionsVariants associated with S. mansoni worm burden were in IL6, FCN2, RNASE3, IL10, IL12B and IL17B gene loci. However only eQTL associations remained significant after Bonferroni correction. In summary, immune balance, pathogen recognition and Th17 pathways may play a role in modulating Schistosoma worm burden. Individuals carrying risk variants may be targeted first in allocation of control efforts to reduce the burden of schistosomiasis in the community.
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- 2023
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9. Transcriptome analysis of peripheral blood of Schistosoma mansoni infected children from the Albert Nile region in Uganda reveals genes implicated in fibrosis pathology.
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Joyce Namulondo, Oscar Asanya Nyangiri, Magambo Phillip Kimuda, Peter Nambala, Jacent Nassuuna, Moses Egesa, Barbara Nerima, Savino Biryomumaisho, Claire Mack Mugasa, Immaculate Nabukenya, Drago Kato, Alison Elliott, Harry Noyes, Robert Tweyongyere, Enock Matovu, Julius Mulindwa, and TrypanoGEN+ research group of the H3Africa consortium
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Arctic medicine. Tropical medicine ,RC955-962 ,Public aspects of medicine ,RA1-1270 - Abstract
Over 290 million people are infected by schistosomes worldwide. Schistosomiasis control efforts focus on mass drug treatment with praziquantel (PZQ), a drug that kills the adult worm of all Schistosoma species. Nonetheless, re-infections have continued to be detected in endemic areas with individuals living in the same area presenting with varying infection intensities. Our objective was to characterize the transcriptome profiles in peripheral blood of children between 10-15 years with varying intensities of Schistosoma mansoni infection living along the Albert Nile in Uganda. RNA extracted from peripheral blood collected from 44 S. mansoni infected (34 high and 10 low by circulating anodic antigen [CAA] level) and 20 uninfected children was sequenced using Illumina NovaSeq S4 and the reads aligned to the GRCh38 human genome. Differential gene expression analysis was done using DESeq2. Principal component analysis revealed clustering of gene expression by gender when S. mansoni infected children were compared with uninfected children. In addition, we identified 14 DEGs between S. mansoni infected and uninfected individuals, 56 DEGs between children with high infection intensity and uninfected individuals, 33 DEGs between those with high infection intensity and low infection intensity and no DEGs between those with low infection and uninfected individuals. We also observed upregulation and downregulation of some DEGs that are associated with fibrosis and its regulation. These data suggest expression of fibrosis associated genes as well as genes that regulate fibrosis in S. mansoni infection. The relatively few significant DEGS observed in children with schistosomiasis suggests that chronic S. mansoni infection is a stealth infection that does not stimulate a strong immune response.
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- 2023
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10. Enabling the genomic revolution in Africa: H3Africa is developing capacity for health-related genomics research in Africa
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The H3Africa Consortium
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- 2014
11. Prevalence and socio-demographic correlates of tobacco and alcohol use in four sub-Saharan African countries: a cross-sectional study of middle-aged adults
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Palwende Romuald Boua, Cassandra Claire Soo, Cornelius Debpuur, Innocent Maposa, Shai Nkoana, Shukri F. Mohamed, Solomon Choma, Abraham Oduro, Gershim Asiki, Lisa K. Micklesfield, Francesc Xavier Gómez-Olivé, Hermann Sorgho, Sumaya Mall, Michèle Ramsay, and as members of AWI-Gen and the H3Africa Consortium
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Adult ,Male ,medicine.medical_specialty ,Alcohol Drinking ,Cross-sectional study ,medicine.medical_treatment ,Population ,03 medical and health sciences ,South Africa ,0302 clinical medicine ,Risk Factors ,Socio-demographic correlates ,Epidemiology ,Tobacco ,medicine ,Prevalence ,Humans ,Adults ,030212 general & internal medicine ,education ,Consumption (economics) ,education.field_of_study ,030505 public health ,Sub-Saharan Africa ,business.industry ,Public health ,Public Health, Environmental and Occupational Health ,Middle Aged ,Tobacco use ,Cross-Sectional Studies ,Smokeless tobacco ,Smoking cessation ,Female ,AWI-gen ,Biostatistics ,Public aspects of medicine ,RA1-1270 ,0305 other medical science ,business ,Alcohol use ,Demography ,Research Article - Abstract
Background Substance misuse is a global public health problem. In addition to social and economic concerns, consumption of tobacco and alcohol is associated with susceptibility to cardiovascular, respiratory, and infectious diseases, cancers, and risk of transition to substance use disorders. African data suggest regional differences in the prevalence and patterns of substance use, but a number of key questions remain. This cross-sectional population-based study of middle-aged adults aims to examine prevalence and socio-demographic correlates of substance use in four sub-Saharan African countries, in rural and urban settings. Methods Participants aged between 40 and 60 years were recruited from six research centres as part of the Africa Wits-INDEPTH partnership for Genomic Research study. Data on patterns of tobacco and alcohol consumption was captured, and the latter further assessed using the CAGE (cut-annoyed-guilty-eye) questionnaire. Results Data from 10,703 participants suggested that more men (68.4%) than women (33.3%) were current substance users. The prevalence of current smoking was significantly higher in men than in women (34.5% vs 2.1%, p Conclusions Regional variation in the patterns and prevalence of substance use was observed across study sites, and in rural and urban settings. The high levels of substance use recorded in this study are of concern due to the increased risk of associated morbidities. Further longitudinal data will be valuable in determining trends in substance misuse in Africa.
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- 2021
12. Ending a diagnostic odyssey—The first case of Takenouchi–Kosaki syndrome in an African patient
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Kaitlyn Flynn, Candice Feben, Lindiwe Lamola, Nadia Carstens, Amanda Krause, Zané Lombard, and for DDD‐Africa as members of the H3Africa Consortium
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Genetics ,Medicine (General) ,business.industry ,TAKENOUCHI-KOSAKI SYNDROME ,Case Report ,CDC42 ,General Medicine ,Case Reports ,030204 cardiovascular system & hematology ,Takenouchi–Kosaki syndrome ,03 medical and health sciences ,0302 clinical medicine ,R5-920 ,030220 oncology & carcinogenesis ,macrothrombocytopenia ,Medicine ,Missense mutation ,whole‐exome sequencing ,business ,Gene ,Likely pathogenic ,Exome sequencing - Abstract
First reported case of Takenouchi–Kosaki syndrome in an African patient with a de novo likely pathogenic missense variant identified in the CDC42 gene., First reported case of Takenouchi–Kosaki syndrome in an African patient with a de novo, likely pathogenic missense variant identified in the CDC42 gene.
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- 2021
13. Candidate gene family-based and case-control studies of susceptibility to high Schistosoma mansoni worm burden in African children: a protocol
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Nyangiri, Oscar A, Edwige, Sokouri A, Koffi, Mathurin, Mewamba, Estelle, Simo, Gustave, Namulondo, Joyce, Mulindwa, Julius, Nassuuna, Jacent, Elliott, Alison, Karume, Kévin, Mumba, Dieudonne, Corstjens, PLAM, Casacuberta-Partal, M, van Dam, GJ, Bucheton, Bruno, Noyes, Harry, Matovu, Enock, and TrypanoGEN+ Research Group of the H3Africa Consortium
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Background: Approximately 25% of the risk of Schistosoma mansoni is associated with host genetic variation. We will test 24 candidate genes, mainly in the T h2 and T h17 pathways, for association with S. mansoni infection intensity in four African countries, using family based and case-control approaches. Methods: Children aged 5-15 years will be recruited in S. mansoni endemic areas of Ivory Coast, Cameroon, Uganda and the Democratic Republic of Congo (DRC). We will use family based (study 1) and case-control (study 2) designs. Study 1 will take place in Ivory Coast, Cameroon, Uganda and the DRC. We aim to recruit 100 high worm burden families from each country except Uganda, where a previous study recruited at least 40 families. For phenotyping, cases will be defined as the 20% of children in each community with heaviest worm burdens as measured by the circulating cathodic antigen (CCA) assay. Study 2 will take place in Uganda. We will recruit 500 children in a highly endemic community. For phenotyping, cases will be defined as the 20% of children with heaviest worm burdens as measured by the CAA assay, while controls will be the 20% of infected children with the lightest worm burdens. Deoxyribonucleic acid (DNA) will be genotyped on the Illumina H3Africa SNP (single nucleotide polymorphisms) chip and genotypes will be converted to sets of haplotypes that span the gene region for analysis. We have selected 24 genes for genotyping that are mainly in the Th2 and Th17 pathways and that have variants that have been demonstrated to be or could be associated with Schistosoma infection intensity. Analysis: In the family-based design, we will identify SNP haplotypes disproportionately transmitted to children with high worm burden. Case-control analysis will detect overrepresentation of haplotypes in extreme phenotypes with correction for relatedness by using whole genome principal components.
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- 2021
14. Friedreich ataxia in a family from Mali, West Africa/Friedreich ataxia in a Malian family
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Cheick A. K. Cissé, Lassana Cissé, Hamidou O. Ba, Oumar Samassékou, Assiatou Simaga, Abdoulaye Taméga, Salimata Diarra, Seybou H. Diallo, Thomas Coulibaly, Salimata Diallo, Abdoulaye Yalcouyé, Alassane B. Maiga, Mohamed Keita, Kenneth H. Fischbeck, Sékou F. Traoré, Cheick O. Guinto, Guida Landouré, and from the H3Africa Consortium
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Medicine (General) ,congenital, hereditary, and neonatal diseases and abnormalities ,Ataxia ,genetic epidemiology ,Black african ,Case Report ,Case Reports ,030204 cardiovascular system & hematology ,Mali ,West africa ,03 medical and health sciences ,R5-920 ,0302 clinical medicine ,West Africa ,medicine ,business.industry ,General Medicine ,Genealogy ,West african ,Genetic epidemiology ,Friedreich ataxia ,Most common inherited ataxia ,030220 oncology & carcinogenesis ,FXN gene ,Medicine ,medicine.symptom ,business - Abstract
Friedreich ataxia is the most common inherited ataxia in the world, but yet to be reported in black African. We report the first genetically confirmed case in a West African family. Studying genetic diseases in populations with diverse backgrounds may give new insights into their pathophysiology for future therapeutic targets.
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- 2021
15. Qualitative study of comprehension of heritability in genomics studies among the Yoruba in Nigeria
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Rasheed O. Taiwo, John Ipadeola, Temilola Yusuf, Faith Fagbohunlu, Gbemisola Jenfa, Sally N. Adebamowo, Clement A. Adebamowo, and the Indigene Study as part of the H3Africa Consortium
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0301 basic medicine ,Health (social science) ,Nigeria ,Indigenous ,Developmental psychology ,Heritability ,03 medical and health sciences ,0302 clinical medicine ,Informed consent ,Yoruba indigenous communities ,Humans ,030212 general & internal medicine ,FGD ,Qualitative Research ,lcsh:R723-726 ,Informed Consent ,Health Policy ,KII ,Yoruba ,Opinion leadership ,Linguistic concepts ,Genomics studies ,Genomics ,Focus group ,language.human_language ,Comprehension ,Issues, ethics and legal aspects ,030104 developmental biology ,Philosophy of medicine ,language ,lcsh:Medical philosophy. Medical ethics ,Psychology ,Research Article ,Qualitative research - Abstract
Background With growth of genomics research in Africa, concern has arisen about comprehension and adequacy of informed consent given the highly technical terms used in this field. We therefore decided to study whether there are linguistic and cultural concepts used to communicate heritability of characters, traits and diseases in an indigenous African population. Methods We conducted Focus Group Discussions among 115 participants stratified by sex, age and socio-economic status and Key Informant Interviews among 25 stakeholders and Key Opinion Leaders among Yoruba living in Ibadan, Nigeria. We used Atlas-ti v.8.3.17 software to analyze the data, using thematic approach. Results The study participants identified several linguistic and cultural concepts including words, proverbs, and aphorisms that are used to describe heritable characters, traits and diseases in their local dialect. These included words that can be appropriated to describe dominant and recessive traits, variations in penetrance and dilution of strength of heritable characteristics by time and inter-marriage. They also suggested that these traits are transmitted by “blood”, and specific partner’s blood may be stronger than the other regardless of sex. Conclusions Indigenous Yoruba populations have words and linguistic concepts that describe the heritability of characters, traits and diseases which can be appropriated to improve comprehension and adequacy of informed consent in genomics research. Our methods are openly available and can be used by genomic researchers in other African communities.
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- 2020
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16. SNPs in IL4 and IFNG show no protective associations with human African trypanosomiasis in the Democratic Republic of the Congo: a case-control study [version 1; peer review: 2 approved]
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Olivier Fataki Asina, Harry Noyes, Bruno Bucheton, Hamidou Ilboudo, Annette MacLeod, Dieudonné Mumba Ngoyi, and TrypanoGEN Group, as members of The H3Africa Consortium
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parasitic diseases ,lcsh:R ,lcsh:Medicine ,lcsh:Q ,lcsh:Science - Abstract
Background: Human African trypanosomiasis (HAT) is a protozoal disease transmitted by tsetse flies. Infection with trypanosomes can lead directly to active HAT or latent infection with no detectable parasites, which may progress to active HAT or to spontaneous self-cure. Genetic variation could explain these differences in the outcome of infection. To test this hypothesis, polymorphisms in 17 candidate genes were tested (APOL1 [G1 and G2], CFH, HLA-A, HPR, HP, IL1B, IL12B, IL12RB1, IL10, IL4R, MIF, TNFA, IL6, IL4, IL8, IFNG, and HLA-G). Methods: Samples were collected in Democratic Republic of the Congo. 233 samples were genotyped: 100 active HAT cases, 33 from subjects with latent infections and 100 negative controls. Commercial service providers genotyped polymorphisms at 96 single nucleotide polymorphisms (SNPs) on 17 genes. Data were analyzed using Plink V1.9 software and R. Loci, with suggestive associations (uncorrected p < 0.05) validated using an additional 594 individuals, including 164 cases and 430 controls. Results: After quality control, 87 SNPs remained in the analysis. Two SNPs in IL4 and two in IFNG were suggestively associated (uncorrected p
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- 2020
17. Adiposity Phenotypes and Subclinical Atherosclerosis in Adults from Sub-Saharan Africa: An H3Africa AWI-Gen Study
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Global Health, Cardiovasculaire Epi Team 5, Cardiovasculaire Epidemiologie, Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, AWI–Gen and the H3Africa Consortium, Global Health, Cardiovasculaire Epi Team 5, Cardiovasculaire Epidemiologie, Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, and AWI–Gen and the H3Africa Consortium
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- 2021
18. Increasing African genomic data generation and sharing to resolve rare and undiagnosed diseases in Africa: a call-to-action by the H3Africa rare diseases working group.
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Lumaka, Aimé, Carstens, Nadia, Devriendt, Koenraad, Krause, Amanda, Kulohoma, Benard, Kumuthini, Judit, Mubungu, Gerrye, Mukisa, John, Nel, Melissa, Olanrewaju, Timothy O., Lombard, Zané, Landouré, Guida, and as members of the Rare Disease Working Group of the H3Africa Consortium
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The rich and diverse genomics of African populations is significantly underrepresented in reference and in disease-associated databases. This renders interpreting the Next Generation Sequencing (NGS) data and reaching a diagnostic more difficult in Africa and for the African diaspora. It increases chances for false positives with variants being misclassified as pathogenic due to their novelty or rarity. We can increase African genomic data by (1) making consent for sharing aggregate frequency data an essential component of research toolkit; (2) encouraging investigators with African data to share available data through public resources such as gnomAD, AVGD, ClinVar, DECIPHER and to use MatchMaker Exchange; (3) educating African research participants on the meaning and value of sharing aggregate frequency data; and (4) increasing funding to scale-up the production of African genomic data that will be more representative of the geographical and ethno-linguistic variation on the continent. The RDWG of H3Africa is hereby calling to action because this underrepresentation accentuates the health disparities. Applying the NGS to shorten the diagnostic odyssey or to guide therapeutic options for rare diseases will fully work for Africans only when public repositories include sufficient data from African subjects. [ABSTRACT FROM AUTHOR]
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- 2022
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19. High-depth African genomes inform human migration and health
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Choudhury, A., Aron, S., Botigue, L. R., Sengupta, D., Botha, G., Bensellak, T., Wells, G., Kumuthini, J., Shriner, D., Fakim, Y. J., Ghoorah, A. W., Dareng, E., Odia, T., Falola, O., Adebiyi, E., Hazelhurst, S., Mazandu, G., Nyangiri, O. A., Mbiyavanga, M., Benkahla, A., Kassim, S. K., Mulder, N., Adebamowo, S. N., Chimusa, E. R., Muzny, D., Metcalf, G., Gibbs, R. A., Rotimi, C., Ramsay, M., Adeyemo, A. A., Lombard, Z., Hanchard, N. A., Bucheton, Bruno (collab.), TrypanoGEN Research Group, and H3Africa Consortium
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The African continent is regarded as the cradle of modern humans and African genomes contain more genetic variation than those from any other continent, yet only a fraction of the genetic diversity among African individuals has been surveyed(1). Here we performed whole-genome sequencing analyses of 426 individualscomprising 50 ethnolinguistic groups, including previously unsampled populations-to explore the breadth of genomic diversity across Africa. We uncovered more than 3 million previously undescribed variants, most of which were found among individuals from newly sampled ethnolinguistic groups, as well as 62 previously unreported loci that are under strong selection, which were predominantly found in genes that are involved in viral immunity, DNA repair and metabolism. We observed complex patterns of ancestral admixture and putative-damaging and novel variation, both within and between populations, alongside evidence that Zambia was a likely intermediate site along the routes of expansion of Bantu-speaking populations. Pathogenic variants in genes that are currently characterized as medically relevant were uncommon-but in other genes, variants denoted as `likely pathogenic' in the ClinVar database were commonly observed. Collectively, these findings refine our current understanding of continental migration, identify gene flow and the response to human disease as strong drivers of genome-level population variation, and underscore the scientific imperative for a broader characterization of the genomic diversity of African individuals to understand human ancestry and improve health.
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- 2020
20. High levels of genetic diversity within nilo-saharan populations : implications for human adaptation
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Mulindwa, J., Noyes, H., Ilboudo, H., Pagani, L., Nyangiri, O., Kimuda, M. P., Ahouty, B., Asina, O. F., Ofon, E., Kamoto, K., Kabore, J. W., Koffi, M., Ngoyi, D. M., Simo, G., Chisi, J., Sidibe, I., Enyaru, J., Simuunza, M., Alibu, P., Jamonneau, Vincent, Camara, M., Tait, A., Hall, N., Bucheton, Bruno, MacLeod, A., Hertz-Fowler, C., Matovu, E., and TrypanoGEN Research Group of the H3Africa Consortium
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Africa contains more human genetic variation than any other continent, but the majority of the population-scale analyses of the African peoples have focused on just two of the four major linguistic groups, the Niger-Congo and Afro-Asiatic, leaving the Nilo-Saharan and Khoisan populations under-represented. In order to assess genetic variation and signatures of selection within a Nilo-Saharan population and between the Nilo-Saharan and Niger-Congo and Afro-Asiatic, we sequenced 50 genomes from the Nilo-Saharan Lugbara population of North-West Uganda and 250 genomes from 6 previously unsequenced Niger-Congo populations. We compared these data to data from a further 16 Eurasian and African populations including the Gumuz, another putative Nilo-Saharan population from Ethiopia. Of the 21 million variants identified in the Nilo-Saharan population, 3.57 million (17%) were not represented in dbSNP and included predicted non-synonymous mutations with possible phenotypic effects. We found greater genetic differentiation between the Nilo-Saharan Lugbara and Gumuz populations than between any two Afro-Asiatic or Niger-Congo populations. F3 tests showed that Gumuz contributed a genetic component to most Niger-Congo B populations whereas Lugabara did not. We scanned the genomes of the Lugbara for evidence of selective sweeps. We found selective sweeps at four loci (SLC24A5, SNX13, TYRP1, and UVRAG) associated with skin pigmentation, three of which already have been reported to be under selection. These selective sweeps point toward adaptations to the intense UV radiation of the Sahel.
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- 2020
21. High-depth African genomes inform human migration and health
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Choudhury, Ananyo, Aron, Shaun, Botigué, Laura R, Sengupta, Dhriti, Botha, Gerrit, Bensellak, Taoufik, Wells, Gordon, Kumuthini, Judit, Shriner, Daniel, Fakim, Yasmina J, Ghoorah, Anisah W, Dareng, Eileen, Odia, Trust, Falola, Oluwadamilare, Adebiyi, Ezekiel, Hazelhurst, Scott, Mazandu, Gaston, Nyangiri, Oscar A, Mbiyavanga, Mamana, Benkahla, Alia, Kassim, Samar K, Mulder, Nicola, Adebamowo, Sally N, Chimusa, Emile R, Muzny, Donna, Metcalf, Ginger, Gibbs, Richard A, TrypanoGEN Research Group, Rotimi, Charles, Ramsay, Michèle, H3Africa Consortium, Adeyemo, Adebowale A, Lombard, Zané, Hanchard, Neil A, National Institutes of Health (US), National Institute of Allergy and Infectious Diseases (US), Wellcome Trust, Generalitat de Catalunya, Ministerio de Economía y Competitividad (España), Bensellak, Taoufik [0000-0002-6151-6276], Shriner, Daniel [0000-0003-1928-5520], Ghoorah, Anisah W [0000-0001-8273-6000], Dareng, Eileen [0000-0003-0802-419X], Hazelhurst, Scott [0000-0002-0581-149X], Nyangiri, Oscar A [0000-0003-2741-2921], Kassim, Samar K [0000-0002-4359-6620], Rotimi, Charles [0000-0001-5759-053X], Ramsay, Michèle [0000-0002-4156-4801], Adeyemo, Adebowale A [0000-0002-3105-3231], Lombard, Zané [0000-0002-7997-2616], Hanchard, Neil A [0000-0003-1925-2665], and Apollo - University of Cambridge Repository
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Gene Flow ,Male ,DNA Repair ,Genetics, Medical ,Human Migration ,Writing ,Population ,Datasets as Topic ,Genomics ,Biology ,Article ,Evolutionary genetics ,Gene flow ,03 medical and health sciences ,0302 clinical medicine ,Genetic variation ,Genetics research ,Humans ,Selection, Genetic ,education ,History, Ancient ,Language ,030304 developmental biology ,Whole genome sequencing ,0303 health sciences ,education.field_of_study ,Genetic diversity ,Multidisciplinary ,Whole Genome Sequencing ,Genome, Human ,Human migration ,business.industry ,Human evolutionary genetics ,Immunity ,Genetic Variation ,Genetics, Population ,Metabolism ,Health ,Evolutionary biology ,Africa ,Next-generation sequencing ,Female ,business ,030217 neurology & neurosurgery - Abstract
TrypanoGEN Research Group., H3Africa Consortium., The African continent is regarded as the cradle of modern humans and African genomes contain more genetic variation than those from any other continent, yet only a fraction of the genetic diversity among African individuals has been surveyed1. Here we performed whole-genome sequencing analyses of 426 individuals—comprising 50 ethnolinguistic groups, including previously unsampled populations—to explore the breadth of genomic diversity across Africa. We uncovered more than 3 million previously undescribed variants, most of which were found among individuals from newly sampled ethnolinguistic groups, as well as 62 previously unreported loci that are under strong selection, which were predominantly found in genes that are involved in viral immunity, DNA repair and metabolism. We observed complex patterns of ancestral admixture and putative-damaging and novel variation, both within and between populations, alongside evidence that Zambia was a likely intermediate site along the routes of expansion of Bantu-speaking populations. Pathogenic variants in genes that are currently characterized as medically relevant were uncommon—but in other genes, variants denoted as ‘likely pathogenic’ in the ClinVar database were commonly observed. Collectively, these findings refine our current understanding of continental migration, identify gene flow and the response to human disease as strong drivers of genome-level population variation, and underscore the scientific imperative for a broader characterization of the genomic diversity of African individuals to understand human ancestry and improve health., We thank the members of the wider H3Africa Consortium (www.h3africa.org). WGS in H3Africa cohorts was supported by a grant from the National Human Genome Research Institute, National Institutes of Health (NIH/NHGRI) U54HG003273. The African Collaborative Center for Microbiome and Genomics Research (ACCME) is funded by NIH/NHGRI grant U54HG006947. The AWI-Gen Collaborative Centre is funded by NIH grant U54HG006938. The Exploring Perspectives on Genomics and Sickle Cell Public Health Interventions was funded by NHGRI/NIH grant U01HG007459. The Clinical and Genetic Studies of Hereditary Neurological Disorders in Mali study was funded by the NHGRI/NIH grant U01HG007044. The Collaborative African Genomics Network (CAfGEN) is funded by the National Institute of Allergy and Infectious Diseases (NIAID) of NIH and the NHGRI of the NIH (U54AI110398). ‘TrypanoGEN: an integrated approach to the identification of genetic determinants of susceptibility to trypanosomiasis’, was funded by the Wellcome Trust (099310/Z/12/Z). L.R.B. was supported by the CERCA Programme/Generalitat de Catalunya and by the Spanish Ministry of Economy and Competitiveness, through the ‘Severo Ochoa Programme for Centres of Excellence in R&D’ 2016–2019 (SEV-2015-0533). N.M. (principal investigator), S.A., G.B., G.W., J.K., Y.J.F., T.O., O.F., E.A., S.H., G. Mazandu, M. Mbiyvanga, A.B., S.K.K., E.R.C. and A. Moussa are funded by the NIH H3ABioNet grant under award number U24HG006941.
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- 2020
22. Engaging research ethics committees to develop an ethics and governance framework for best practices in genomic research and biobanking in Africa: the H3Africa model
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Paulina Tindana, Aminu Yakubu, Ciara Staunton, Alice Matimba, Katherine Littler, Ebony Madden, Nchangwi Syntia Munung, Jantina de Vries, and as members of the H3Africa Consortium
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Genetic Research ,Health (social science) ,Best practice ,Genomic research ,education ,0603 philosophy, ethics and religion ,03 medical and health sciences ,0302 clinical medicine ,Stakeholder Participation ,Political science ,Humans ,030212 general & internal medicine ,Human heredity ,Biological Specimen Banks ,Research ethics ,lcsh:R723-726 ,Health Policy ,Corporate governance ,Community Participation ,06 humanities and the arts ,Biobank ,Issues, ethics and legal aspects ,Philosophy of medicine ,Africa ,Commentary ,Engineering ethics ,060301 applied ethics ,lcsh:Medical philosophy. Medical ethics ,Ethics Committees, Research - Abstract
In the past decade, there has been an increase in genomic research and biobanking activities in Africa. Research initiatives such as the Human Heredity and Health in Africa (H3Africa) Consortium are contributing to the development of scientific capacity and infrastructure to support these studies on the continent. Despite this growth, genomic research and biobanking have raised important ethical challenges for key research stakeholders, including members of research ethics committees. One of these is the limited ethical and regulatory frameworks to guide the review and conduct of genomic studies, particularly in Africa. This paper is a reflection on a series of consultative activities with research ethics committees in Africa which informed the development of an ethics and governance framework for best practices in genomic research and biobanking in Africa. The paper highlights the engagement process and the lessoned learned.
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- 2019
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23. Association of APOL1 renal disease risk alleles with Trypanosoma brucei rhodesiense infection outcomes in the northern part of Malawi
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Kelita Kamoto, Harry Noyes, Peter Nambala, Edward Senga, Janelisa Musaya, Benjamin Kumwenda, Bruno Bucheton, Annette Macleod, Anneli Cooper, Caroline Clucas, Christiane Herz-Fowler, Enock Matove, Arthur M Chiwaya, John E Chisi, and TrypanoGEN Research Group as members of The H3Africa Consortium
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0301 basic medicine ,Male ,Trypanosoma brucei rhodesiense ,Candidate gene ,Malawi ,Heredity ,RC955-962 ,Geographical Locations ,0302 clinical medicine ,Arctic medicine. Tropical medicine ,Zoonoses ,Genotype ,Medicine and Health Sciences ,African trypanosomiasis ,Uganda ,Protozoans ,biology ,Eukaryota ,Middle Aged ,Apolipoprotein L1 ,3. Good health ,Genetic Mapping ,Infectious Diseases ,Disease Progression ,Cytokines ,Female ,Kidney Diseases ,Public aspects of medicine ,RA1-1270 ,Research Article ,Neglected Tropical Diseases ,Adult ,Genetic Markers ,Trypanosoma ,Genotyping ,030231 tropical medicine ,Single-nucleotide polymorphism ,Variant Genotypes ,Trypanosoma brucei ,Research and Analysis Methods ,Polymorphism, Single Nucleotide ,African Trypanosomiasis ,Molecular Genetics ,03 medical and health sciences ,Trypanosomiasis ,parasitic diseases ,medicine ,Parasitic Diseases ,Genetics ,Trypanosoma Brucei ,Humans ,Genetic Predisposition to Disease ,Allele ,Molecular Biology Techniques ,Molecular Biology ,Alleles ,Genetic Association Studies ,Protozoan Infections ,Public Health, Environmental and Occupational Health ,Case-control study ,Organisms ,Biology and Life Sciences ,medicine.disease ,biology.organism_classification ,Tropical Diseases ,Parasitic Protozoans ,030104 developmental biology ,Trypanosomiasis, African ,Case-Control Studies ,Immunology ,People and Places ,Africa - Abstract
Trypanosoma brucei (T.b.) rhodesiense is the cause of the acute form of human African trypanosomiasis (HAT) in eastern and southern African countries. There is some evidence that there is diversity in the disease progression of T.b. rhodesiense in different countries. HAT in Malawi is associated with a chronic haemo-lymphatic stage infection compared to other countries, such as Uganda, where the disease is acute with more marked neurological impairment. This has raised the question of the role of host genetic factors in infection outcomes. A candidate gene association study was conducted in the northern region of Malawi. This was a case-control study involving 202 subjects, 70 cases and 132 controls. All individuals were from one area; born in the area and had been exposed to the risk of infection since birth. Ninety-six markers were genotyped from 17 genes: IL10, IL8, IL4, HLA-G, TNFA, IL6, IFNG, MIF, APOL, HLA-A, IL1B, IL4R, IL12B, IL12R, HP, HPR, and CFH. There was a strong significant association with APOL1 G2 allele (p = 0.0000105, OR = 0.14, CI95 = [0.05–0.41], BONF = 0.00068) indicating that carriers of the G2 allele were protected against T.b. rhodesiense HAT. SNP rs2069845 in IL6 had raw p < 0.05, but did not remain significant after Bonferroni correction. There were no associations found with the other 15 candidate genes. Our finding confirms results from other studies that the G2 variant of APOL1 is associated with protection against T.b. rhodesiense HAT., Author summary Though some work has been done on the genetics of trypanosome infections in animals, relatively little is known about the genetics of human African trypanosomiasis (HAT) infections. To test whether any variants are associated with reduced or increased risk of trypanosomiasis, 96 variants in 17 genes were genotyped in patients diagnosed with T. b. rhodesiense HAT and individuals without the disease in this study. From the 96 variants, only one variant G2 in the APOL1 gene was found to be strongly associated with protection from trypanosomiasis. The results reported here will contribute to the knowledge of the role of human genetics in disease progression, which could offer opportunities for development of much needed new diagnostics and intervention strategies.
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- 2019
24. Classical Cardiovascular Risk Factors and HIV are Associated With Carotid Intima-Media Thickness in Adults From Sub-Saharan Africa : Findings From H3Africa AWI-Gen Study
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as members and collaborators of AWI‐Gen and the H3Africa Consortium
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sub-Saharan Africa ,epidemiological transition ,prevention ,cardiovascular disease ,carotid intima-media thickness ,Journal Article - Abstract
Background Studies on the determinants of carotid intima-media thickness ( CIMT ), a marker of sub-clinical atherosclerosis, mostly come from white, Asian, and diasporan black populations. We present CIMT data from sub-Saharan Africa, which is experiencing a rising burden of cardiovascular diseases and infectious diseases. Methods and Results The H3 (Human Hereditary and Health) in Africa's AWI-Gen (African-Wits-INDEPTH partnership for Genomic) study is a cross-sectional study conducted in adults aged 40 to 60 years from Burkina Faso, Kenya, Ghana, and South Africa. Cardiovascular disease risk and ultrasonography of the CIMT of right and left common carotids were measured. Multivariable linear and mixed-effect multilevel regression modeling was applied to determine factors related to CIMT. Data included 8872 adults (50.8% men), mean age of 50±6 years with age- and sex-adjusted mean (±SE) CIMT of 640±123μm. Participants from Ghana and Burkina Faso had higher CIMT compared with other sites. Age (β = 6.77, 95%CI [6.34-7.19]), body mass index (17.6[12.5-22.8]), systolic blood pressure (7.52[6.21-8.83]), low-density lipoprotein cholesterol (5.08[2.10-8.06]) and men (10.3[4.75- 15.9]) were associated with higher CIMT. Smoking was associated with higher CIMT in men. High-density lipoprotein cholesterol (-12.2 [-17.9- -6.41]), alcohol consumption (-13.5 [-19.1--7.91]) and HIV (-8.86 [-15.7--2.03]) were inversely associated with CIMT. Conclusions Given the rising prevalence of cardiovascular diseases risk factors in sub-Saharan Africa, atherosclerotic diseases may become a major pan-African epidemic unless preventive measures are taken particularly for prevention of hypertension, obesity, and smoking. HIV -specific studies are needed to fully understand the association between HIV and CIMT in sub-Saharan Africa.
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- 2019
25. A novel mutation in the GARS gene in a Malian family with Charcot‐Marie‐Tooth disease
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Abdoulaye Yalcouyé, Seybou H. Diallo, Thomas Coulibaly, Lassana Cissé, Salimata Diallo, Oumar Samassékou, Salimata Diarra, Dramane Coulibaly, Mohamed Keita, Cheick O. Guinto, Kenneth Fischbeck, Guida Landouré, and The H3Africa Consortium
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Adult ,Glycine-tRNA Ligase ,Male ,0301 basic medicine ,Proband ,lcsh:QH426-470 ,Mutation, Missense ,Disease ,030105 genetics & heredity ,Biology ,Mali ,Clinical Reports ,CMT2D ,03 medical and health sciences ,Atrophy ,Charcot-Marie-Tooth Disease ,Gene duplication ,GARS ,Genetics ,medicine ,Humans ,Missense mutation ,Molecular Biology ,Gene ,Genetics (clinical) ,Genetic testing ,Clinical Report ,medicine.diagnostic_test ,CMT ,Middle Aged ,medicine.disease ,Pedigree ,3. Good health ,lcsh:Genetics ,030104 developmental biology ,Genetic epidemiology ,Female ,novel mutation - Abstract
Background Charcot‐Marie‐Tooth (CMT) disease is a very heterogeneous neurological condition with more than 90 reported genetic entities. It is the most common inherited peripheral neuropathy; however, cases are rarely reported in sub‐Saharan Africa. In addition, only few families, mostly of Caucasian ancestry, have been reported to have Charcot‐Marie‐Tooth disease type 2D (CMT2D) mutations. To date no case of CMT2D was reported in Africa. We present here a consanguineous family with CMT phenotype in which a novel mutation in the GARS (glycyl‐tRNA synthetase) gene was identified. Methods Patients were examined thoroughly and nerve conduction studies (NCS) were performed. DNA from the proband was used for CMT gene panel testing (including 50 genes, PMP22 duplication and mtDNA). Putative mutations were verified in all available family members to check for segregation. Results Two individuals, a male and a female, were found to be affected. Symptoms started in their teenage years with muscle weakness and atrophy in hands. Later, distal involvement of the lower limbs was noticed. Patients complained of minor sensory impairment. NCS showed no response in the upper as well as the lower limbs. Genetic testing surprisingly identified a novel heterozygous missense mutation c.794C>A (p.Ser265Tyr) in the GARS gene associated with CMT2D. This variant segregated with the disease in the family and was also seen in the mother who presented no symptoms. Conclusion This is the first report of a genetically confirmed CMT2D case in Africa, expanding its genetic epidemiology. Increasing access to genetic testing may reveal more novel CMT variants or genes in the African population that could be relevant to other populations and further our understanding of their mechanism.
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- 2019
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26. Association between IL1 gene polymorphism and human African trypanosomiasis in populations of sleeping sickness foci of southern Cameroon
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Elvis Ofon, Harry Noyes, Vincent Ebo'o Eyanga, Flobert Njiokou, Mathurin Koffi, Pythagore Fogue, Christiane Hertz-Fowler, Annette MacLeod, Enock Matovu, Gustave Simo, and TrypanoGEN Research Group, as members of The H3Africa Consortium
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0301 basic medicine ,Male ,Heredity ,Trypanosoma brucei gambiense ,Artificial Gene Amplification and Extension ,Polymerase Chain Reaction ,Geographical Locations ,0302 clinical medicine ,Zoonoses ,Genotype ,Medicine and Health Sciences ,African trypanosomiasis ,Cameroon ,Child ,Genetics ,Aged, 80 and over ,Protozoans ,biology ,lcsh:Public aspects of medicine ,Neglected Diseases ,Eukaryota ,Middle Aged ,3. Good health ,Genetic Mapping ,Infectious Diseases ,Female ,Research Article ,Neglected Tropical Diseases ,Adult ,Risk ,Trypanosoma ,lcsh:Arctic medicine. Tropical medicine ,Adolescent ,lcsh:RC955-962 ,030231 tropical medicine ,Single-nucleotide polymorphism ,Variant Genotypes ,Trypanosoma brucei ,Research and Analysis Methods ,Polymorphism, Single Nucleotide ,African Trypanosomiasis ,Molecular Genetics ,03 medical and health sciences ,Young Adult ,Trypanosomiasis ,parasitic diseases ,medicine ,Parasitic Diseases ,Humans ,Genetic Predisposition to Disease ,Molecular Biology Techniques ,Molecular Biology ,Alleles ,Genetic Association Studies ,Aged ,Protozoan Infections ,Public Health, Environmental and Occupational Health ,Organisms ,Biology and Life Sciences ,lcsh:RA1-1270 ,medicine.disease ,biology.organism_classification ,Tropical Diseases ,Parasitic Protozoans ,Minor allele frequency ,030104 developmental biology ,Trypanosomiasis, African ,Genetic Loci ,Case-Control Studies ,People and Places ,Africa ,Gene polymorphism - Abstract
Background Human African Trypanosomiasis (HAT) is a neglected tropical disease caused by infections due to Trypanosoma brucei subspecies. In addition to the well-established environmental and behavioural risks of becoming infected, there is evidence for a genetic component to the response to trypanosome infection. We undertook a candidate gene case-control study to investigate genetic associations further. Methodology We genotyped one polymorphism in each of seven genes (IL1A, IL1RN, IL4RN, IL6, HP, HPR, and HLA-G) in 73 cases and 250 controls collected from 19 ethno-linguistic subgroups stratified into three major ethno-linguistic groups, 2 pooled ethno-linguistic groups and 11 ethno-linguistic subgroups from three Cameroonian HAT foci. The seven polymorphic loci tested consisted of three SNPs, three variable numbers of tandem repeat (VNTR) and one INDEL. Results We found that the genotype (TT) and minor allele (T) of IL1A gene as well as the genotype 1A3A of IL1RN were associated with an increased risk of getting Trypanosoma brucei gambiense and develop HAT when all data were analysed together and also when stratified by the three major ethno-linguistic groups, 2 pooled ethno-linguistic subgroups and 11 ethno-linguistic subgroups. Conclusion This study revealed that one SNP rs1800794 of IL1A and one VNTR rs2234663 of IL1RN were associated with the increased risk to be infected by Trypanosoma brucei gambiense and develop sleeping sickness in southern Cameroon. The minor allele T and the genotype TT of SNP rs1800794 in IL1A as well as the genotype 1A3A of IL1RN rs2234663 VNTR seem to increase the risk of getting Trypanosoma brucei gambiense infections and develop sleeping sickness in southern Cameroon., Author summary Human African Trypanosomiasis (HAT), or sleeping sickness, is a parasitic disease caused by flagellated parasites of the genus Trypanosoma. This disease has been included into the WHO roadmap for neglected tropical diseases with elimination as a public health problem targeted for 2020 and the interruption of transmission to humans for 2030. To achieve these elimination and interruption goals, it is important to identify and understand the factors that may hamper these goals. Understanding the contribution of human genetics to the response of trypanosome infections is important for the development of new control strategies. In this study, polymorphism in seven genes was investigated between controls and sleeping sickness patients of three sleeping sickness foci of Southern Cameroon in order to see if there is any association with the development of disease. Results of this study have shown that the genotype (TT) and minor allele (T) of IL1A gene and the genotype 1A3A VNTR of IL1RN are associated with an increased risk of getting T. b. gambiense infections and develop sleeping sickness in major ethno-linguistic groups of the Cameroonian population. They suggest that the association between host genetic determinants and the susceptibility to T. b. gambiense infections could vary according to the population studied. These results will improve our knowledge on the role of human genetics determinants and the risk to be infected by T. b. gambiense and develop sleeping sickness. They could thus lead to the identification of novel biomarkers which could open a frame work for the development of new diagnostics, treatments and intervention strategies.
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- 2019
27. Genetic associations with carotid intima-media thickness link to atherosclerosis with sex-specific effects in sub-Saharan Africans.
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Boua, Palwende Romuald, Brandenburg, Jean-Tristan, Choudhury, Ananyo, Sorgho, Hermann, Nonterah, Engelbert A., Agongo, Godfred, Asiki, Gershim, Micklesfield, Lisa, Choma, Solomon, Gómez-Olivé, Francesc Xavier, Hazelhurst, Scott, Tinto, Halidou, Crowther, Nigel J., Mathew, Christopher G., Ramsay, Michèle, AWI-Gen Study, and the H3Africa Consortium
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CAROTID intima-media thickness ,ATHEROSCLEROSIS ,GENOME-wide association studies ,GENETIC sex determination ,CARDIOLOGICAL manifestations of general diseases ,LINKAGE disequilibrium - Abstract
Atherosclerosis precedes the onset of clinical manifestations of cardiovascular diseases (CVDs). We used carotid intima-media thickness (cIMT) to investigate genetic susceptibility to atherosclerosis in 7894 unrelated adults (3963 women, 3931 men; 40 to 60 years) resident in four sub-Saharan African countries. cIMT was measured by ultrasound and genotyping was performed on the H3Africa SNP Array. Two new African-specific genome-wide significant loci for mean-max cIMT, SIRPA (p = 4.7E-08), and FBXL17 (p = 2.5E-08), were identified. Sex-stratified analysis revealed associations with one male-specific locus, SNX29 (p = 6.3E-09), and two female-specific loci, LARP6 (p = 2.4E-09) and PROK1 (p = 1.0E-08). We replicate previous cIMT associations with different lead SNPs in linkage disequilibrium with SNPs primarily identified in European populations. Our study find significant enrichment for genes involved in oestrogen response from female-specific signals. The genes identified show biological relevance to atherosclerosis and/or CVDs, sex-differences and transferability of signals from non-African studies. Genetic studies of disease-relevant traits have mostly been performed on European populations. Here, the authors perform a genome-wide association study for carotid intima-media thickness, in sub-Saharan African samples, finding population-specific and sex-specific loci. [ABSTRACT FROM AUTHOR]
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- 2022
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28. Association of APOL1 renal disease risk alleles with Trypanosoma brucei rhodesiense infection outcomes in the northern part of Malawi
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Kamoto, K., Noyes, H., Nambala, P., Senga, E., Musaya-Mwalija, J., Kumwenda, B., Bucheton, Bruno, Macleod, A., Herz-Fowler, C., Matovu, E., Chiwaya, A. M., Chisi, J. E., and TrypanoGEN Research Group H3Africa Consortium
- Subjects
parasitic diseases - Abstract
Trypanosoma brucei (T.b.) rhodesiense is the cause of the acute form of human African trypanosomiasis (HAT) in eastern and southern African countries. There is some evidence that there is diversity in the disease progression of T.b. rhodesiense in different countries. HAT in Malawi is associated with a chronic haemo-lymphatic stage infection compared to other countries, such as Uganda, where the disease is acute with more marked neurological impairment. This has raised the question of the role of host genetic factors in infection outcomes. A candidate gene association study was conducted in the northern region of Malawi. This was a case-control study involving 202 subjects, 70 cases and 132 controls. All individuals were from one area; born in the area and had been exposed to the risk of infection since birth. Ninety-six markers were genotyped from 17 genes: IL10, IL8, IL4, HLA-G, TNFA, IL6, IFNG, MIF, APOL, HLA-A, IL1B, IL4R, IL12B, IL12R, HP, HPR, and CFH. There was a strong significant association with APOL1 G2 allele (p = 0.0000105, OR = 0.14, CI95 = [0.05-0.41], BONF = 0.00068) indicating that carriers of the G2 allele were protected against T.b. rhodesiense HAT. SNP rs2069845 in IL6 had raw p < 0.05, but did not remain significant after Bonferroni correction. There were no associations found with the other 15 candidate genes. Our finding confirms results from other studies that the G2 variant of APOL1 is associated with protection against T.b. rhodesiense HAT.
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- 2019
29. Correction: The burden of dyslipidaemia and factors associated with lipid levels among adults in rural northern Ghana: An AWI-Gen sub-study
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Godfred Agongo, Engelbert Adamwaba Nonterah, Cornelius Debpuur, Lucas Amenga-Etego, Stuart Ali, Abraham Oduro, Nigel J Crowther, Michèle Ramsay, and as members of AWI-Gen and the H3Africa Consortium
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Multidisciplinary ,lcsh:R ,lcsh:Medicine ,lcsh:Q ,lcsh:Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0206326.].
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- 2019
30. Clearance of Type-Specific, Low-Risk, and High-Risk Cervical Human Papillomavirus Infections in HIV-Negative and HIV-Positive Women
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Sally N. Adebamowo, Ayotunde Famooto, Eileen O. Dareng, Oluwatoyosi Olawande, Olayinka Olaniyan, Richard Offiong, Clement A. Adebamowo, and for the ACCME Research Group as part of the H3Africa Consortium
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Adult ,Cancer Research ,medicine.medical_specialty ,Human immunodeficiency virus (HIV) ,HIV Infections ,Cervix Uteri ,medicine.disease_cause ,lcsh:RC254-282 ,03 medical and health sciences ,0302 clinical medicine ,5. Gender equality ,Risk Factors ,Internal medicine ,Humans ,Original Report ,Medicine ,030212 general & internal medicine ,Human papillomavirus ,Papillomaviridae ,business.industry ,Proportional hazards model ,Papillomavirus Infections ,Hazard ratio ,HPV infection ,Type specific ,HIV ,virus diseases ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,3. Good health ,Oncology ,030220 oncology & carcinogenesis ,Population study ,Female ,business ,Clearance - Abstract
Purpose There is a dearth of data on clearance of cervical human papillomavirus (HPV) infection among women in West Africa. We examined the clearance of low-risk (lr) and high-risk (hr) cervical HPV infections, and the factors associated with these measures in HIV-negative and HIV-positive women. Methods We studied 630 Nigerian women involved in a study of HPV infection using short polymerase chain reaction fragment-10 assay and line probe assay-25. Research nurses used a cervical brush to collect samples of exfoliated cervical cells from all the study participants. Cox proportional hazards models were used to estimate associations between HIV and HPV infections. Results The mean age of the study participants was 38 (standard deviation, ± 8) years; 51% were HIV positive. The rate of clearing any HPV infection was 2.0% per month among all women in the study population, 2.5% per month among HIV-negative women, and 1.6% per month, among HIV-positive women. The clearance rate per 1,000 person-months of observation for any lrHPV infection and any hrHPV infection were 9.21 and 8.83, respectively, for HIV-negative women, and 9.38 and 9.37, respectively, for HIV-positive women. In multivariate models, the hazard ratios for HIV-positive compared with HIV-negative women were 0.85 (95% CI, 0.51 to 1.43; P = .55) and 0.95 (95% CI, 0.54 to 1.65; P = .85) for cleared infections with any lrHPV and any hrHPV, respectively. The hazard ratio for HIV-positive compared with HIV-negative women was 0.39 (95% CI, 0.17 to 0.88; P = .02) for cleared infections with any multiple HPV and 0.13 (95% CI, 0.03 to 0.58; P = .007) for cleared infections with multiple hrHPV. Conclusion In this study population, we observed that HIV-positive women were less likely to clear infections with multiple hrHPV types.
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- 2018
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31. Socio-demographic and behavioural determinants of body mass index among an adult population in rural Northern Ghana : the AWI-Gen study
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Nonterah, Engelbert Adamwaba, Debpuur, Cornelius, Agongo, Godfred, Amenga-Etego, Lucas, Crowther, Nigel J., Ramsay, Michèle, Rexford Oduro, Abraham, and as members of AWI-Gen and the H3Africa Consortium
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BMI ,socio-demographic and behavioural risk ,Health Policy ,Public Health, Environmental and Occupational Health ,pesticides ,rural Northern Ghana ,Cardiometabolic diseases - Abstract
Background: Obesity and associated cardiometabolic diseases are increasing in urban sub-Saharan Africa due to a complex epidemiological and nutritional transition. Related data on rural communities is scarce. Objectives: The study characterized the socio-demographic and behavioural factors influencing body mass index (BMI) among adults in rural Northern Ghana Methods: A population-based cross-sectional study involving adults aged 40–60 years residing in the Kassena-Nankana districts was undertaken. Demographic, socio-economic and behavioural data were collected along with measures of anthropometry. We determined factors associated with BMI among women and men. Results: A total of 2014 adults were studied. The median age was 51 (IQR 45–57) years and 54% were women. The prevalence of overweight/obesity was higher among women than men (18.4% vs. 7.2%; p
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- 2018
32. Regional and sex-specific variation in BMI distribution in four sub-Saharan African countries: The H3Africa AWI-Gen study
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Michèle Ramsay, Nigel J. Crowther, Godfred Agongo, Stuart A. Ali, Gershim Asiki, Romuald P. Boua, F. Xavier Gómez-Olivé, Kathleen Kahn, Christopher Khayeka-Wandabwa, Felistas Mashinya, Lisa Micklesfield, Freedom Mukomana, Engelbert A. Nonterah, Cassandra Soo, Hermann Sorgho, Alisha N. Wade, Ryan G. Wagner, Marianne Alberts, Scott Hazelhurst, Catherine Kyobutungi, Shane A. Norris, Abraham R. Oduro, Osman Sankoh, Halidou Tinto, Stephen Tollman, and as members of AWI-Gen and the H3Africa Consortium
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Male ,obesity ,Distribution (economics) ,Body Mass Index ,0302 clinical medicine ,Risk Factors ,CMD ,Prevalence ,030212 general & internal medicine ,media_common ,2. Zero hunger ,Geography ,030503 health policy & services ,Health Policy ,lcsh:Public aspects of medicine ,1. No poverty ,Middle Aged ,Sex specific ,3. Good health ,Variation (linguistics) ,Regional variation ,Female ,Original Article ,0305 other medical science ,Adult ,Adolescent ,Demographic history ,media_common.quotation_subject ,Genetic genealogy ,Black People ,03 medical and health sciences ,BMI ,medicine ,Humans ,Sex Distribution ,SSA ,Africa South of the Sahara ,Aged ,sex-specific variation ,business.industry ,Public Health, Environmental and Occupational Health ,regional variation ,lcsh:RA1-1270 ,Overweight ,medicine.disease ,Obesity ,Cross-Sectional Studies ,Social Class ,business ,human activities ,Demography ,Diversity (politics) - Abstract
Background: African populations are characterised by diversity at many levels including: demographic history, genetic ancestry, language, wealth, socio-political landscape, culture and behaviour. Several of these have a profound impact on body fat mass. Obesity, a key risk factor for cardiovascular and metabolic diseases, in the wake of the epidemiological and health transitions across the continent, requires detailed analysis together with other major risk factors. Objective: To compare regional and sex-specific body mass index (BMI) distributions, using a cross-sectional study design, in adults aged 40–60 years across six study sites in four sub-Saharan African (SSA) countries and to compare the determinants of BMI at each. Methods: Anthropometric measurements were standardised across sites and BMI calculated. Median BMI and prevalence of underweight, lean, overweight and obesity were compared between the sexes and across sites. Data from multivariable linear regression models for the principal determinants of BMI were summarised from the site-specific studies. Results: BMI was calculated in 10,702 participants (55% female) and was significantly higher in women than men at nearly all sites. The highest prevalence of obesity was observed at the three South African sites (42.3–66.6% in women and 2.81–17.5% in men) and the lowest in West Africa (1.25–4.22% in women and 1.19–2.20% in men). Across sites, higher socio-economic status and educational level were associated with higher BMI. Being married and increased dietary intake were associated with higher BMI in some communities, whilst smoking and alcohol intake were associated with lower BMI, as was HIV infection in the regions where it was prevalent. Conclusion: In SSA there is a marked variation in the prevalence of obesity both regionally and between men and women. Our data suggest that the drive for social upliftment within Africa will be associated with rising levels of obesity, which will require the initiation of targeted sex-specific intervention programmes across specific African communities.
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- 2018
33. Prevalence and socio-demographic correlates of tobacco and alcohol use in four sub-Saharan African countries: a cross-sectional study of middle-aged adults.
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Boua, Palwende Romuald, Soo, Cassandra Claire, Debpuur, Cornelius, Maposa, Innocent, Nkoana, Shai, Mohamed, Shukri F., Choma, Solomon, Oduro, Abraham, Asiki, Gershim, Micklesfield, Lisa K., Gómez-Olivé, Francesc Xavier, Sorgho, Hermann, Mall, Sumaya, Ramsay, Michèle, and as members of AWI-Gen and the H3Africa Consortium
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PUBLIC health ,TOBACCO use ,ALCOHOL drinking ,MIDDLE-aged persons - Abstract
Background: Substance misuse is a global public health problem. In addition to social and economic concerns, consumption of tobacco and alcohol is associated with susceptibility to cardiovascular, respiratory, and infectious diseases, cancers, and risk of transition to substance use disorders. African data suggest regional differences in the prevalence and patterns of substance use, but a number of key questions remain. This cross-sectional population-based study of middle-aged adults aims to examine prevalence and socio-demographic correlates of substance use in four sub-Saharan African countries, in rural and urban settings.Methods: Participants aged between 40 and 60 years were recruited from six research centres as part of the Africa Wits-INDEPTH partnership for Genomic Research study. Data on patterns of tobacco and alcohol consumption was captured, and the latter further assessed using the CAGE (cut-annoyed-guilty-eye) questionnaire.Results: Data from 10,703 participants suggested that more men (68.4%) than women (33.3%) were current substance users. The prevalence of current smoking was significantly higher in men than in women (34.5% vs 2.1%, p < 0.001). Smokeless tobacco was used more by women than men (14.4% vs 5.3%, p < 0.001). Current smoking was associated with alcohol consumption in men, and smoking cessation in men was associated with being a former drinker, having higher socio-economic status, and if married or cohabiting. Current alcohol consumption was higher in men, compared to women (60.3% vs 29.3%), and highest in men from Soweto (70.8%) and women from Nanoro (59.8%). The overall prevalence of problematic alcohol consumption among men was 18.9%, and women 7.3%. Men were significantly more likely to develop problematic drinking patterns, and this was more common in those who were divorced or widowed, and in current smokers.Conclusions: Regional variation in the patterns and prevalence of substance use was observed across study sites, and in rural and urban settings. The high levels of substance use recorded in this study are of concern due to the increased risk of associated morbidities. Further longitudinal data will be valuable in determining trends in substance misuse in Africa. [ABSTRACT FROM AUTHOR]- Published
- 2021
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34. Classical Cardiovascular Risk Factors and HIV are Associated With Carotid Intima-Media Thickness in Adults From Sub-Saharan Africa: Findings From H3Africa AWI-Gen Study
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Global Health, Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Cardiovasculaire Epi Team 9, Cardiovasculaire Epi Team 5, as members and collaborators of AWI‐Gen and the H3Africa Consortium, Global Health, Circulatory Health, JC onderzoeksprogramma Cardiovasculaire Epidemiologie, Cardiovasculaire Epi Team 9, Cardiovasculaire Epi Team 5, and as members and collaborators of AWI‐Gen and the H3Africa Consortium
- Published
- 2019
35. Genetic substructure and complex demographic history of South African Bantu speakers.
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Sengupta, Dhriti, Choudhury, Ananyo, Fortes-Lima, Cesar, Aron, Shaun, Whitelaw, Gavin, Bostoen, Koen, Gunnink, Hilde, Chousou-Polydouri, Natalia, Delius, Peter, Tollman, Stephen, Gómez-Olivé, F. Xavier, Norris, Shane, Mashinya, Felistas, Alberts, Marianne, AWI-Gen Study, H3Africa Consortium, Hazelhurst, Scott, Schlebusch, Carina M., and Ramsay, Michèle
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SOUTH African history ,GENE flow ,DEMOGRAPHIC characteristics ,POPULATION dynamics ,IRON Age - Abstract
South Eastern Bantu-speaking (SEB) groups constitute more than 80% of the population in South Africa. Despite clear linguistic and geographic diversity, the genetic differences between these groups have not been systematically investigated. Based on genome-wide data of over 5000 individuals, representing eight major SEB groups, we provide strong evidence for fine-scale population structure that broadly aligns with geographic distribution and is also congruent with linguistic phylogeny (separation of Nguni, Sotho-Tswana and Tsonga speakers). Although differential Khoe-San admixture plays a key role, the structure persists after Khoe-San ancestry-masking. The timing of admixture, levels of sex-biased gene flow and population size dynamics also highlight differences in the demographic histories of individual groups. The comparisons with five Iron Age farmer genomes further support genetic continuity over ~400 years in certain regions of the country. Simulated trait genome-wide association studies further show that the observed population structure could have major implications for biomedical genomics research in South Africa. Despite linguistic and geographic diversity in South Eastern Bantu-speaking (SEB) groups of South Africa, genetic variation in these groups has not been investigated in depth. Here, the authors analyse genome-wide data from 5056 individuals, providing insights into demographic history across SEB groups. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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36. Candidate genes-based investigation of susceptibility to Human African Trypanosomiasis in Côte d'Ivoire
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Bernardin Ahouty, Mathurin Koffi, Hamidou Ilboudo, Gustave Simo, Enock Matovu, Julius Mulindwa, Christiane Hertz-Fowler, Bruno Bucheton, Issa Sidibé, Vincent Jamonneau, Annette MacLeod, Harry Noyes, Simon-Pierre N'Guetta, and TrypanoGEN Research Group as members of The H3Africa Consortium
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Male ,0301 basic medicine ,False discovery rate ,Candidate gene ,Trypanosoma brucei gambiense ,0302 clinical medicine ,African trypanosomiasis ,Child ,Aged, 80 and over ,Genetics ,Principal Component Analysis ,0303 health sciences ,lcsh:Public aspects of medicine ,Middle Aged ,Apolipoprotein L1 ,3. Good health ,Intramolecular Oxidoreductases ,Phenotype ,Infectious Diseases ,symbols ,Female ,Lipoproteins, HDL ,Research Article ,Adult ,medicine.medical_specialty ,lcsh:Arctic medicine. Tropical medicine ,Adolescent ,lcsh:RC955-962 ,030231 tropical medicine ,Single-nucleotide polymorphism ,Biology ,Polymorphism, Single Nucleotide ,Young Adult ,symbols.namesake ,03 medical and health sciences ,Molecular genetics ,medicine ,Humans ,SNP ,Genetic Predisposition to Disease ,Macrophage Migration-Inhibitory Factors ,Genetic Association Studies ,Aged ,030304 developmental biology ,Genetic diversity ,Interleukin-6 ,Tumor Necrosis Factor-alpha ,Public Health, Environmental and Occupational Health ,Tropical disease ,lcsh:RA1-1270 ,medicine.disease ,Apolipoproteins ,Cote d'Ivoire ,Trypanosomiasis, African ,Bonferroni correction ,030104 developmental biology ,Case-Control Studies ,Immunology ,Interleukin-4 ,Trypanosomiasis - Abstract
Human African Trypanosomiasis (HAT) or sleeping sickness is a Neglected Tropical Disease. Long regarded as an invariably fatal disease, there is increasing evidence that infection by T. b. gambiense can result in a wide range of clinical outcomes, including latent infections, which are long lasting infections with no parasites detectable by microscopy. The determinants of this clinical diversity are not well understood but could be due in part to parasite or host genetic diversity in multiple genes, or their interactions. A candidate gene association study was conducted in Côte d’Ivoire using a case-control design which included a total of 233 subjects (100 active HAT cases, 100 controls and 33 latent infections). All three possible pairwise comparisons between the three phenotypes were tested using 96 SNPs in16 candidate genes (IL1, IL4, IL4R, IL6, IL8, IL10, IL12, IL12R, TNFA, INFG, MIF, APOL1, HPR, CFH, HLA-A and HLA-G). Data from 77 SNPs passed quality control. There were suggestive associations at three loci in IL6 and TNFA in the comparison between active cases and controls, one SNP in each of APOL1, MIF and IL6 in the comparison between latent infections and active cases and seven SNP in IL4, HLA-G and TNFA between latent infections and controls. No associations remained significant after Bonferroni correction, but the Benjamini Hochberg false discovery rate test indicated that there were strong probabilities that at least some of the associations were genuine. The excess of associations with latent infections despite the small number of samples available suggests that these subjects form a distinct genetic cluster different from active HAT cases and controls, although no clustering by phenotype was observed by principle component analysis. This underlines the complexity of the interactions existing between host genetic polymorphisms and parasite diversity., Author summary Since it was first identified, human African trypanosomiasis (HAT) or sleeping sickness has been described as invariably fatal. Recent data however suggest that infection by T. b. gambiense can result in a wide range of clinical outcomes in its human host including long lasting infections, that can be detected by the presence of antibodies, but in which parasites cannot be seen by microscopy; these cases are known as latent infections. While the factors determining, this varied response have not been clearly characterized, the effectors of the immune responses have been partially implicated as key players. We collected samples from people with active HAT, latent infections and controls in endemic foci in the Côte d’Ivoire. We tested the role of single nucleotide polymorphisms (SNPs) in 16 genes on susceptibility/resistance to HAT by means of a candidate gene association study. There was some evidence that variants of the genes for IL4, IL6, APOL1, HLAG, MIF and TNFA modified the risk of developing HAT. These proteins regulate the inflammatory response to many infections or are directly involved in killing the parasites. In this study, the results were statistically weak and would be inconclusive on their own, however other studies have also found associations in these genes, increasing the chance that the variants that we have identified play a genuine role in the response to trypanosome infection in Côte D’Ivoire.
- Published
- 2017
37. Qualitative study of comprehension of heritability in genomics studies among the Yoruba in Nigeria.
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Taiwo, Rasheed O., Ipadeola, John, Yusuf, Temilola, Fagbohunlu, Faith, Jenfa, Gbemisola, Adebamowo, Sally N., Adebamowo, Clement A., and Indigene Study as part of the H3Africa Consortium
- Subjects
GENOMICS ,COMPREHENSION ,HERITABILITY ,TREND setters ,AFRICANS ,FOCUS groups ,YORUBA (African people) ,ETHNOLOGY research ,MENTAL depression ,PATHOLOGICAL psychology ,RESEARCH funding - Abstract
Background: With growth of genomics research in Africa, concern has arisen about comprehension and adequacy of informed consent given the highly technical terms used in this field. We therefore decided to study whether there are linguistic and cultural concepts used to communicate heritability of characters, traits and diseases in an indigenous African population.Methods: We conducted Focus Group Discussions among 115 participants stratified by sex, age and socio-economic status and Key Informant Interviews among 25 stakeholders and Key Opinion Leaders among Yoruba living in Ibadan, Nigeria. We used Atlas-ti v.8.3.17 software to analyze the data, using thematic approach.Results: The study participants identified several linguistic and cultural concepts including words, proverbs, and aphorisms that are used to describe heritable characters, traits and diseases in their local dialect. These included words that can be appropriated to describe dominant and recessive traits, variations in penetrance and dilution of strength of heritable characteristics by time and inter-marriage. They also suggested that these traits are transmitted by "blood", and specific partner's blood may be stronger than the other regardless of sex.Conclusions: Indigenous Yoruba populations have words and linguistic concepts that describe the heritability of characters, traits and diseases which can be appropriated to improve comprehension and adequacy of informed consent in genomics research. Our methods are openly available and can be used by genomic researchers in other African communities. [ABSTRACT FROM AUTHOR]- Published
- 2020
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38. Socio-demographic and behavioural determinants of body mass index among an adult population in rural Northern Ghana: the AWI-Gen study
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Global Health, Nonterah, Engelbert Adamwaba, Debpuur, Cornelius, Agongo, Godfred, Amenga-Etego, Lucas, Crowther, Nigel J., Ramsay, Michèle, Rexford Oduro, Abraham, as members of AWI-Gen and the H3Africa Consortium, Global Health, Nonterah, Engelbert Adamwaba, Debpuur, Cornelius, Agongo, Godfred, Amenga-Etego, Lucas, Crowther, Nigel J., Ramsay, Michèle, Rexford Oduro, Abraham, and as members of AWI-Gen and the H3Africa Consortium
- Published
- 2018
39. Gender differences in sociodemographic and behavioural factors associated with BMI in an adult population in rural Burkina Faso - an AWI-Gen sub-study.
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Boua, Romuald Palwende, Sorgho, Hermann, Rouamba, Toussaint, Nakanabo Diallo, Seydou, Bognini, Joel Dofinissery, Konkobo, Sophie Z, Valia, Daniel, Lingani, Moussa, Ouoba, Serge, Tougma, Alain S, Bihoun, Biebo, Crowther, Nigel John, Norris, Shane A, Ramsay, Michèle, Tinto, Halidou, as members of AWI-Gen and the H3Africa Consortium, Boua, Romuald Palwende, Sorgho, Hermann, Rouamba, Toussaint, Nakanabo Diallo, Seydou, Bognini, Joel Dofinissery, Konkobo, Sophie Z, Valia, Daniel, Lingani, Moussa, Ouoba, Serge, Tougma, Alain S, Bihoun, Biebo, Crowther, Nigel John, Norris, Shane A, Ramsay, Michèle, Tinto, Halidou, and as members of AWI-Gen and the H3Africa Consortium
- Abstract
The global health transition is linked with an increased burden of non-communicable diseases with cardiovascular diseases leading the epidemic. In sub-Saharan Africa (SSA), the prevalence of obesity has increased during the past decades and there is a need to investigate the associated driving factors. In Burkina Faso obesity remains low, especially in rural areas. In this study we recruited middle-aged adults, as part of a larger study on genetic and environmental contributions to cardiometabolic disease among Africans., info:eu-repo/semantics/published
- Published
- 2018
40. Regulation of genomic and biobanking research in Africa: a content analysis of ethics guidelines, policies and procedures from 22 African countries
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de Vries, Jantina, Munung, Syntia N, Matimba, Alice, McCurdy, Sheryl, Ouwe Missi Oukem-Boyer, Odile, Staunton, Ciara, Yakubu, Aminu, Tindana, Paulina, H3Africa Consortium, Department of Medicine, and Faculty of Health Sciences
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Health (social science) ,Biomedical Research ,Research Subjects ,Best practice ,education ,Guidelines as Topic ,0603 philosophy, ethics and religion ,Health(social science) ,Ethics, Research ,03 medical and health sciences ,0302 clinical medicine ,Information ethics ,Humans ,030212 general & internal medicine ,Sociology ,Biological Specimen Banks ,Informed Consent ,Information Dissemination ,Health Policy ,06 humanities and the arts ,Genomics ,Applied ethics ,Biobank ,Research Personnel ,Social Control, Formal ,Data sharing ,Issues, ethics and legal aspects ,Policy ,Philosophy of medicine ,Law ,Africa ,Science policy ,Engineering ethics ,060301 applied ethics ,Thematic analysis ,Ethics Committees, Research ,Research Article - Abstract
Background: The introduction of genomics and biobanking methodologies to the African research context has also introduced novel ways of doing science, based on values of sharing and reuse of data and samples. This shift raises ethical challenges that need to be considered when research is reviewed by ethics committees, relating for instance to broad consent, the feedback of individual genetic findings, and regulation of secondary sample access and use. Yet existing ethics guidelines and regulations in Africa do not successfully regulate research based on sharing, causing confusion about what is allowed, where and when. \ud \ud Methods: In order to understand better the ethics regulatory landscape around genomic research and biobanking, we conducted a comprehensive analysis of existing ethics guidelines, policies and other similar sources. We sourced 30 ethics regulatory documents from 22 African countries. We used software that assists with qualitative data analysis to conduct a thematic analysis of these documents.\ud \ud Results: Surprisingly considering how contentious broad consent is in Africa, we found that most countries allow the use of this consent model, with its use banned in only three of the countries we investigated. In a likely\ud response to fears about exploitation, the export of samples outside of the continent is strictly regulated, sometimes in conjunction with regulations around international collaboration. We also found that whilst an essential and critical component of ensuring ethical best practice in genomics research relates to the governance framework that accompanies sample and data sharing, this was most sparingly covered in the guidelines.\ud \ud Conclusions: There is a need for ethics guidelines in African countries to be adapted to the changing science policy landscape, which increasingly supports principles of openness, storage, sharing and secondary use. Current guidelines are not pertinent to the ethical challenges that such a new orientation raises, and therefore fail to provide accurate guidance to ethics committees and researchers.
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- 2017
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41. Sickle cell disease and H3Africa: enhancing genomic research on cardiovascular diseases in African patients
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Wonkam, Ambroise, Makani, Julie, Ofori-Aquah, Solomon, Nnodu, Obiageli E, Treadwell, Marsha, Royal, Charmaine, Ohene-Frempong, Kwaku, and Members of the H3Africa Consortium
- Subjects
Sickle Cell Disease ,Research ,Human Genome ,Anemia ,Hematology ,Cardiovascular ,Medical and Health Sciences ,Sickle Cell ,Rare Diseases ,Blood ,Good Health and Well Being ,Cardiovascular System & Hematology ,Cardiovascular Diseases ,Clinical Research ,General & Internal Medicine ,Members of the H3Africa Consortium ,Africa ,Prevalence ,Genetics ,Humans ,2.1 Biological and endogenous factors ,Genetic Predisposition to Disease ,Aetiology ,Genome-Wide Association Study - Abstract
BackgroundSickle cell disease (SCD) has a high prevalence in sub-Saharan Africa. There are several cardiovascular phenotypes in SCD that contribute to its morbidity and mortality.DiscussionSCD is characterised by marked clinical variability, with genetic factors playing key modulating roles. Studies in Tanzania and Cameroon have reported that singlenucleotide polymorphisms in BCL11A and HBS1L-MYB loci and co-inheritance of alpha-thalassaemia impact on foetal haemoglobin levels and clinical severity. The prevalence of overt stroke among SCD patients in Cameroon (6.7%) and Nigeria (8.7%) suggests a higher burden than in high-income countries. There is also some evidence of high burden of kidney disease and pulmonary hypertension in SCD; however, the burden and genetics of these cardiovascular conditions have seldom been investigated in Africa.ConclusionsSeveral H3Africa projects are focused on cardiovascular diseases and present major opportunities to build genome-based research on existing SCD platforms in Africa to transform the health outcomes of patients.
- Published
- 2015
42. Cohort Profile: African Collaborative Center for Microbiome and Genomics Research's (ACCME's) Human Papillomavirus (HPV) and Cervical Cancer Study.
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Adebamowo, Sally N., Dareng, Eileen O., Famooto, Ayotunde O., Offiong, Richard, Olaniyan, Olayinka, Obende, Kayode, Adebayo, Amos, Ologun, Sanni, Alabi, Bunmi, Achara, Peter, Bakare, Rasheed A., Odutola, Michael, Olawande, Oluwatoyosi, Okuma, James, Odonye, George, Adebiyi, Ruxton, Dakum, Patrick, Adebamowo, Clement A., and ACCME Research Group as part of the H3Africa Consortium
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CERVICAL cancer ,PAPILLOMAVIRUS diseases ,CERVICAL intraepithelial neoplasia ,CANCER vaccines ,EPIDEMIOLOGY of cancer ,BLACK people ,LONGITUDINAL method ,PAPILLOMAVIRUSES ,RESEARCH funding ,CERVIX uteri tumors ,GENOMICS - Published
- 2017
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43. African partnerships through the H3Africa Consortium bring a genomic dimension to longitudinal population studies on the continent.
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Ramsay, Michèle, Sankoh, Osman, and as members of the AWI-Gen study and the H3Africa Consortium
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POPULATION & economics ,BUSINESS partnerships ,LONGITUDINAL method ,PUBLICATIONS ,CONFERENCES & conventions ,COMPARATIVE studies ,INTERNATIONAL relations ,RESEARCH methodology ,MEDICAL cooperation ,RESEARCH ,EVALUATION research ,GENOMICS ,ETHICS - Published
- 2016
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44. Engaging research ethics committees to develop an ethics and governance framework for best practices in genomic research and biobanking in Africa: the H3Africa model.
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Tindana, Paulina, Yakubu, Aminu, Staunton, Ciara, Matimba, Alice, Littler, Katherine, Madden, Ebony, Munung, Nchangwi Syntia, de Vries, Jantina, and as members of the H3Africa Consortium
- Subjects
RESEARCH ethics ,ETHICS committees ,BEST practices ,SCIENTIFIC development ,CAPACITY building - Abstract
In the past decade, there has been an increase in genomic research and biobanking activities in Africa. Research initiatives such as the Human Heredity and Health in Africa (H3Africa) Consortium are contributing to the development of scientific capacity and infrastructure to support these studies on the continent. Despite this growth, genomic research and biobanking have raised important ethical challenges for key research stakeholders, including members of research ethics committees. One of these is the limited ethical and regulatory frameworks to guide the review and conduct of genomic studies, particularly in Africa. This paper is a reflection on a series of consultative activities with research ethics committees in Africa which informed the development of an ethics and governance framework for best practices in genomic research and biobanking in Africa. The paper highlights the engagement process and the lessoned learned. [ABSTRACT FROM AUTHOR]
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- 2019
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45. A Novel Splice Site Variant in COL6A1 Causes Ullrich Congenital Muscular Dystrophy in a Consanguineous Malian Family
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Alassane Baneye Maiga, Ibrahim Pamanta, Salia Bamba, Lassana Cissé, Salimata Diarra, Sidi Touré, Abdoulaye Yalcouyé, Seydou Diallo, Salimata Diallo, Fousseyni Kané, Seybou Hassane Diallo, Hamidou Oumar Ba, Cheick Oumar Guinto, Kenneth Fischbeck, Guida Landoure, Idrissa Ahmadou Cissé, and The H3Africa Consortium
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Africa ,COL6A1 ,collagen VI‐related muscular dystrophies ,Mali ,splicing variant ,Ullrich congenital muscular dystrophy ,Genetics ,QH426-470 - Abstract
ABSTRACT Background Congenital muscular dystrophies (CMDs) are diverse early‐onset conditions affecting skeletal muscle and connective tissue. This group includes collagen VI‐related dystrophies such as Ullrich congenital muscular dystrophy (UCMD) and Bethlem myopathy (BM), caused by mutations in the COL6A1, COL6A2 and COL6A3 genes. We report a consanguineous Malian family with three siblings affected by UCMD due to a novel homozygous splice site variant in the COL6A1 gene. Methods After obtaining consent, three affected siblings and their relatives underwent physical examinations by specialists and laboratory tests where possible. DNA was extracted from peripheral blood for genetic testing, including Whole Exome Sequencing (WES). Putative variants were confirmed through Sanger Sequencing and assessed for pathogenicity using in silico tools. Results The three siblings and their healthy parents, from a consanguineous marriage, presented with early‐onset progressive muscle weakness, walking difficulty, proximal motor deficits, severe muscle atrophy, hypotonia, skeletal deformities, joint hyperlaxity, ankyloses at the elbows and knees, keloid scars and dental crowding. No cardiac involvement was detected and creatine kinase (CK) levels were normal. All had low serum calcium levels, treated with oral supplements. Needle myography indicated myopathic patterns. WES identified a novel splice site variant in the first intron of COL6A1 (c.98‐1G>C), which segregated with the disease within the family. This variant is predicted to cause exon 2 skipping in COL6A1, with a high CADD score of 33 and Splice AI predicting it as deleterious. Conclusion We identified a novel COL6A1 variant in a consanguineous family, highlighting the need for further studies in larger African cohorts to enhance genetic epidemiology and prepare for future therapeutic research.
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- 2024
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46. Population-based study of the reproductive risk factors for transvaginal ultrasound diagnosed uterine fibroids in Nigerian women
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Clement A. Adebamowo, The ACCME Research Group as part of the H3Africa Consortium, and Sally N. Adebamowo
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Medicine ,Science - Abstract
Abstract There has been no previous systematic, epidemiological study of the reproductive risk factors for uterine fibroids (UF) in African populations despite African women having the highest burden of UF in the world. Improved knowledge of the associations between UF and reproductive factors would contribute to better understanding of the etiology of UF and may suggest novel opportunities for prevention and therapeutic interventions. We used nurse administered questionnaires to survey the demographic and reproductive risk factors of UF among 484 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria, and who had transvaginal ultrasound diagnosis (TVUS). We used logistic regression models to the evaluate associations between reproductive risk factors and UF, adjusted for significant covariates. In our multivariable logistic regression models, we found inverse associations with number of children (OR = 0.83, 95%CI = 0.74–0.93, p-value = 0.002), parity (OR = 0.41, 95%CI = 0.24–0.73, p-value = 0.002), history of any type of abortion (OR = 0.53, 95%CI = 0.35–0.82, p-value = 0.004), duration of use of Depot Medroxyprogesterone Acetate (DMPA) (p-value for trend = 0.02), menopausal status (OR = 0.48, 95%CI = 0.27–0.84, p-value = 0.01), and a non-linear positive association with age (OR = 1.04, 95%CI = 1.01–1.07, p-value = 0.003). Other reproductive risk factors that have been reported in other populations (age at menarche and menopause, and oral contraceptives) were not associated with UF in this study. Our study confirms some of the reproductive risk factors for UF that have been found in other populations and shows that some of them are stronger in the Nigerian population. The associations we found with DMPA suggest opportunities for further research to understand the mechanisms of action of progesterone and its analogues in the etiology of UF, their potential use for prevention and treatment of UF.
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- 2023
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47. Validation of self-report of uterine fibroid diagnosis using a transvaginal ultrasound scan
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Clement A. Adebamowo, Imran O. Morhason-Bello, The ACCME Research Group as part of the H3Africa Consortium, and Sally N. Adebamowo
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Medicine ,Science - Abstract
Abstract Self-report of uterine fibroids (UF) has been used for epidemiologic research in different environments. Given the dearth of studies on the epidemiology of UF in Sub-Saharan Africa (SSA), it is valuable to evaluate its performance as a potential tool for much needed research on this common neoplasm in SSA women. We conducted a cross-sectional study of self-report of UF compared with transvaginal ultrasound diagnosis (TVUS) among 486 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria. We used log-binomial regression models to compute the classification, sensitivity, specificity, and predictive values of self-report compared to TVUS, adjusted for significant covariates. The prevalence of UF on TVUS was 45.1% (219/486) compared to 5.4% (26/486) based on self-report of abdominal ultrasound scan and 7.2% (35/486) based on report of healthcare practitioner’s diagnosis. Self-report correctly classified 39.5% of the women compared to TVUS in multivariable adjusted models. The multivariable adjusted sensitivity of self-report of healthcare worker diagnosis was 38.8%, specificity was 74.5%, positive predictive value (PPV) was 55.6%, and negative predictive value (NPV) was 59.8%. For self-reported abdominal ultrasound diagnosis, the multivariable adjusted sensitivity was 40.6%, specificity was 75.3%, PPV was 57.4%, and NPV was 60.6%. Self-report significantly underestimates the prevalence of UF and is not accurate enough for epidemiological research on UF. Future studies of UF should use population-based designs and more accurate diagnostic tools such as TVUS.
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- 2023
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48. Retrospective file review shows limited genetic services fail most patients – an argument for the implementation of exome sequencing as a first-tier test in resource-constrained settings
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Emma K. Wiener, James Buchanan, Amanda Krause, Zané Lombard, and for the DDD-Africa Study, as members of the H3Africa Consortium
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Low- and middle-income countries ,Genetic services ,Exome sequencing ,Developmental disorders ,Diagnostic guidelines ,Medicine - Abstract
Abstract Background Exome sequencing is recommended as a first-line investigation for patients with a developmental delay or intellectual disability. This approach has not been implemented in most resource-constraint settings, including Africa, due to the high cost of implementation. Instead, patients have limited access to services and testing options. Here, we evaluate the effectiveness of a limited genetic testing strategy and contrast the findings to a conceivable outcome if exome sequencing were available instead. Results A retrospective audit of 934 patient files presenting to a medical genetics clinic in South Africa showed that 83% of patients presented with developmental delay as a clinical feature. Patients could be divided into three groups, representing distinct diagnostic pathways. Patient Group A (18%; mean test cost $131) were confirmed with aneuploidies, following a simple, inexpensive test. Patient Group B (25%; mean test cost $140) presented with clinically recognizable conditions but only 39% received a genetic diagnostic confirmation due to limited testing options. Patient Group C – the largest group (57%; mean test cost $337) – presented with heterogenous conditions and DD, and 92% remained undiagnosed after limited available testing was performed. Conclusions Patients with DD are the largest group of patients seen in medical genetics clinics in South Africa. When clinical features are not distinct, limited testing options drastically restricts diagnostic yield. A cost- and time analysis shows most patients would benefit from first-line exome sequencing, reducing their individual diagnostic odysseys.
- Published
- 2023
- Full Text
- View/download PDF
49. Increasing African genomic data generation and sharing to resolve rare and undiagnosed diseases in Africa: a call-to-action by the H3Africa rare diseases working group
- Author
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Aimé Lumaka, Nadia Carstens, Koenraad Devriendt, Amanda Krause, Benard Kulohoma, Judit Kumuthini, Gerrye Mubungu, John Mukisa, Melissa Nel, Timothy O. Olanrewaju, Zané Lombard, Guida Landouré, and as members of the Rare Disease Working Group of the H3Africa Consortium
- Subjects
Data sharing ,NGS interpretation ,Diversity ,Reference database ,Medicine - Abstract
Abstract The rich and diverse genomics of African populations is significantly underrepresented in reference and in disease-associated databases. This renders interpreting the Next Generation Sequencing (NGS) data and reaching a diagnostic more difficult in Africa and for the African diaspora. It increases chances for false positives with variants being misclassified as pathogenic due to their novelty or rarity. We can increase African genomic data by (1) making consent for sharing aggregate frequency data an essential component of research toolkit; (2) encouraging investigators with African data to share available data through public resources such as gnomAD, AVGD, ClinVar, DECIPHER and to use MatchMaker Exchange; (3) educating African research participants on the meaning and value of sharing aggregate frequency data; and (4) increasing funding to scale-up the production of African genomic data that will be more representative of the geographical and ethno-linguistic variation on the continent. The RDWG of H3Africa is hereby calling to action because this underrepresentation accentuates the health disparities. Applying the NGS to shorten the diagnostic odyssey or to guide therapeutic options for rare diseases will fully work for Africans only when public repositories include sufficient data from African subjects.
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- 2022
- Full Text
- View/download PDF
50. Genetic associations with carotid intima-media thickness link to atherosclerosis with sex-specific effects in sub-Saharan Africans
- Author
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Palwende Romuald Boua, Jean-Tristan Brandenburg, Ananyo Choudhury, Hermann Sorgho, Engelbert A. Nonterah, Godfred Agongo, Gershim Asiki, Lisa Micklesfield, Solomon Choma, Francesc Xavier Gómez-Olivé, Scott Hazelhurst, Halidou Tinto, Nigel J. Crowther, Christopher G. Mathew, Michèle Ramsay, AWI-Gen Study, and the H3Africa Consortium
- Subjects
Science - Abstract
Genetic studies of disease-relevant traits have mostly been performed on European populations. Here, the authors perform a genome-wide association study for carotid intima-media thickness, in sub-Saharan African samples, finding population-specific and sex-specific loci.
- Published
- 2022
- Full Text
- View/download PDF
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