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Diagnosis of individuals affected by monogenic disorders was significantly improved by next-generation sequencing targeting clinically relevant genes. Whole exomes yield a large number of variants that require several filtering steps, prioritization, and pathogenicity classification. Among the criteria recommended by ACMG, those that rely on population databases critically affect analyses of individuals with underrepresented ancestries. Population-specific allelic frequencies need consideration when characterizing potential deleteriousness of variants. An orthogonal input for classification is annotation of variants previously classified as pathogenic as a criterion that provide supporting evidence widely sourced at ClinVar. We used a whole-genome dataset from a census-based cohort of 1,171 elderly individuals from São Paulo, Brazil, highly admixed, and unaffected by severe monogenic disorders, to investigate if pathogenic assertions in ClinVar are enriched with higher proportions of European ancestry, indicating bias. Potential loss of function (pLOF) variants were filtered from 4,250 genes associated with Mendelian disorders and annotated with ClinVar assertions. Over 1,800 single nucleotide pLOF variants were included, 381 had non-benign assertions. Among carriers (N = 463), average European ancestry was significantly higher than noncarriers (N = 708; p = .011). pLOFs in genomic contexts of non-European local ancestries were nearly three times less likely to have any ClinVar entry (OR = 0.353; p

Background/objectives: Admixed populations are a resource to study the global genetic architecture of complex phenotypes, which is critical, considering that non-European populations are severely underrepresented in genomic studies. Here, we study the genetic architecture of BMI in children, young adults, and elderly individuals from the admixed population of Brazil. Subjects/methods: Leveraging admixture in Brazilians, whose chromosomes are mosaics of fragments of Native American, European, and African origins, we used genome-wide data to perform admixture mapping/fine-mapping of body mass index (BMI) in three Brazilian population-based cohorts from Northeast (Salvador), Southeast (Bambui), and South (Pelotas). Results: We found significant associations with African-associated alleles in children from Salvador (PALD1 and ZMIZ1 genes), and in young adults from Pelotas (NOD2 and MTUS2 genes). More importantly, in Pelotas, rs114066381, mapped in a potential regulatory region, is significantly associated only in females (p = 2.76e-06). This variant is rare in Europeans but with frequencies of similar to 3% in West Africa and has a strong female-specific effect (95% CI: 2.32-5.65 kg/m(2) per each A allele). We confirmed this sex-specific association and replicated its strong effect for an adjusted fat mass index in the same Pelotas cohort, and for BMI in another Brazilian cohort from Sao Paulo (Southeast Brazil). A meta-analysis confirmed the significant association. Remarkably, we observed that while the frequency of rs114066381-A allele ranges from 0.8 to 2.1% in the studied populations, it attains similar to 9% among women with morbid obesity from Pelotas, Sao Paulo, and Bambui. The effect size of rs114066381 is at least five times higher than the FTO SNPs rs9939609 and rs1558902, already emblematic for their high effects. Conclusions: We identified six candidate SNPs associated with BMI. rs114066381 stands out for its high effect that was replicated and its high frequency in women with morbid obesity. We demonstrate how admixed populations are a source of new relevant phenotype-associated genetic variants.

Tuberculosis (TB) is one of the most fatal infectious diseases, caused by the aerobic bacteria Mycobacterium tuberculosis. It is estimated that one-third of the world’s population is infected with the latent (LTB) version of this disease, with only 5-10% of infected individuals developing its active (ATB) form. Pulmonary adenocarcinoma (PA) is the most common and diverse form of primary lung carcinoma. The simultaneous or sequential occurrence of TB and lung cancer in patients has been widely reported and is known to be an issue for diagnosis and surgical treatment. Raising evidence shows that patients cured of TB represent a group at risk for developing PA. In this work, using sRNA-sequencing, we evaluated the expression patterns of circulating small RNAs available in exosomes extracted from blood samples of Peruvian patients affected by latent tuberculosis, active tuberculosis, or pulmonary adenocarcinoma. Differential expression analysis revealed a set of 24 microRNAs perturbed in these diseases, revealing potential biomarker candidates for the Peruvian population. Most of these miRNAs are normally expressed in healthy lung tissue and are potential regulators of different shared and unique KEGG pathways related to cancers, infectious diseases, and immunology.

Background: In Peru, 32,970 people were diagnosed with tuberculosis (TB) in 2019. Although TB treatment is effective, 3.4%–13% is associated with significant adverse drug reactions (ADR), considering drug-induced liver injury (DILI) as the most prevalent. Among the first-line anti-TB drugs, isoniazid (INH) is primarily responsible for the occurrence of DILI. INH is metabolized in the liver by the enzymes N-acetyltransferase-2 (NAT2) and Cytochrome P450 2E1 (CYP2E1). Based on the previous studies, we hypothesized that the interactions between slow CYP2E1 genotype and NAT2 slow acetylators will induce DILI in TB patients. Methods: In this cross-sectional study, all 377 participants completed their anti-TB treatment, and we genotyped SNPs: rs1041983, rs1801280, rs1799929, rs1799930, rs1208, and rs1799931 for NAT2 and rs3813867 and rs2031920 for CYP2E1. Results: We found that rapid, intermediate, and slow NAT2 acetylator were 15%, 38%, and 47%, respectively, in the general population. Intermediate NAT2 acetylator is the least prevalent among patients with adverse reactions (p = 0.024). We did not confirm our hypothesis, however, we found that the combination of intermediate NAT2 acetylators and CYP2E1 c1/c1 genotype significantly protected (OR = 0.16; p = 0.049) against the development of DILI in our population. Conclusion: We propose that the presence of NAT2 intermediate and CYP2E1 c1/c1 genotype could help in therapeutic drug monitoring, and optimize its therapeutic benefits while minimizing its risk for side effects or toxicity.

PDE4B (phosphodiesterase-4B) has an important role in cancer and in pharmacology of some disorders, such as inflammatory diseases. Remarkably in Native Americans, PDE4B variants are associated with acute lymphoblastic leukemia (ALL) relapse, as this gene modulates sensitivity of glucocorticoids used in ALL chemotherapy. PDE4B allele rs6683977.G, associated with genomic regions of Native American origin in US-Hispanics (admixed among Native Americans, Europeans, and Africans), increases ALL relapse risk, contributing to an association between Native American ancestry and ALL relapse that disappeared with an extra-phase of chemotherapy. This result insinuates that indigenous populations along the Americas may have high frequencies of rs6683977.G, but this has never been corroborated. We studied ancestry and PDE4B diversity in 951 healthy individuals from nine Latin American populations. In non-admixed Native American populations rs6683977.G has frequencies greater than 90%, is in linkage disequilibrium with other ALL relapse associated and regulatory variants in PDE4B-intron-7, conforming haplotypes showing their highest worldwide frequencies in Native Americans (0.82). Our findings inform the discussion on the pertinence of an extra-phase of chemotherapy in Native American populations, and exemplifies how knowledge generated in US-Hispanics is relevant for their even more neglected and vulnerable Native American ancestors along the American continent.

Made available in DSpace on 2022-04-29T08:46:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2022-12-01 National Institute of General Medical Sciences As whole-genome sequencing (WGS) becomes the gold standard tool for studying population genomics and medical applications, data on diverse non-European and admixed individuals are still scarce. Here, we present a high-coverage WGS dataset of 1,171 highly admixed elderly Brazilians from a census-based cohort, providing over 76 million variants, of which ~2 million are absent from large public databases. WGS enables identification of ~2,000 previously undescribed mobile element insertions without previous description, nearly 5 Mb of genomic segments absent from the human genome reference, and over 140 alleles from HLA genes absent from public resources. We reclassify and curate pathogenicity assertions for nearly four hundred variants in genes associated with dominantly-inherited Mendelian disorders and calculate the incidence for selected recessive disorders, demonstrating the clinical usefulness of the present study. Finally, we observe that whole-genome and HLA imputation could be significantly improved compared to available datasets since rare variation represents the largest proportion of input from WGS. These results demonstrate that even smaller sample sizes of underrepresented populations bring relevant data for genomic studies, especially when exploring analyses allowed only by WGS. Human Genome and Stem Cell Research Center University of São Paulo, SP Department of Genetics and Evolutionary Biology Biosciences Institute University of São Paulo, SP Hospital Israelita Albert Einstein, SP Instituto da Criança Faculdade de Medicina da Universidade de São Paulo, SP Orthopedic Research Labs Boston Children’s Hospital and Department of Genetics Harvard Medical School Laboratório DASA Laboratory of Genome Structure and Ageing European Research Institute for the Biology of Ageing University Medical Center Groningen São Paulo State University (UNESP) Molecular Genetics and Bioinformatics Laboratory School of Medicine, State of São Paulo São Paulo State University (UNESP) Department of Pathology School of Medicine, State of São Paulo Departamento de Química Faculdade de Filosofia Ciências e Letras de Ribeirão Preto Universidade de São Paulo, São Paulo Centro de Oncologia Molecular Hospital Sirio-Libanes Department of Biochemistry Institute of Chemistry University of São Paulo São Paulo Bioinformatics Graduate program University of São Paulo Departamento de Genética Ecologia e Evolução Instituto de Ciências Biológicas Universidade Federal de Minas Gerais, MG Núcleo de Ensino e Pesquisa Instituto Mário Penna, MG Laboratorio de Biotecnologia y Biologia Molecular Instituto Nacional de Salud Universidad de Huánuco Division of Cancer Epidemiology and Genetics National Cancer Institute Instituto de Saúde Coletiva Universidade Federal da Bahia, BA Center for Data and Knowledge Integration for Health Institute Gonçalo Muniz Fundação Oswaldo Cruz, BA Instituto de Pesquisas René Rachou Fundação Oswaldo Cruz, MG Programa De Pós-Graduação em Saúde Pública Universidade Federal de Minas Gerais, MG Programa de Pós-Graduação em Epidemiologia Universidade Federal de Pelotas, RS Mosaico Translational Genomics Initiative Universidade Federal de Minas Gerais, MG Facultad de Salud Pública y Administración Universidad Peruana Cayetano Heredia Instituto de Estudos Avançados Transdisciplinares Universidade Federal de Minas Gerais, MG Medical-Surgical Nursing Department School of Nursing University of São Paulo, SP Epidemiology Department Public Health School University of São Paulo, SP São Paulo State University (UNESP) Molecular Genetics and Bioinformatics Laboratory School of Medicine, State of São Paulo São Paulo State University (UNESP) Department of Pathology School of Medicine, State of São Paulo National Institute of General Medical Sciences: R01 GM075091

Background We determined the frequency of genetic polymorphisms in three anti‐TB drug metabolic proteins previously reported: N‐acetyltransferase 2 (NAT2), cytochrome P450 2E1 (CYP2E1), and arylacetamide deacetylase (AADAC) within a Peruvian population in a cohort of TB patients. Methods We genotyped SNPs rs1041983, rs1801280, rs1799929, rs1799930, rs1208, and rs1799931 for NAT2; rs3813867 and rs2031920 for CYP2E1; and rs1803155 for AADAC in 395 participants completed their antituberculosis treatment. Results Seventy‐four percent of the participants are carriers of slow metabolizer genotypes: NAT2*5, NAT2*6, and NAT2*7, which increase the sensitivity of INH at low doses and increase the risk of drug‐induced liver injuries. Sixty‐four percent are homozygous for the wild‐type CYP2E1*1A allele, which could increase the risk of hepatotoxicity. However, 16% had a NAT2 fast metabolizer phenotype which could increase the risk of acquiring resistance to INH, thereby increasing the risk of multidrug‐resistant (MDR) or treatment failure. The frequency of rs1803155 (AADAC*2 allele) was higher (99.9%) in Peruvians than in European American, African American, Japanese, and Korean populations. Conclusions This high prevalence of slow metabolizers for isoniazid in the Peruvian population should be further studied and considered to help individualize drug regimens, especially in countries with a great genetic diversity like Peru. These data will help the Peruvian National Tuberculosis Control Program develop new strategies for therapies., High prevalence of slow metabolizers for isoniazid in the Peruvian population should be further studied and considered to help individualize drug regimens, especially in countries with a great genetic diversity like Peru.

Peru is a pluricultural and ethnically diverse country located in middle west of South America. It is the fourth largest country (1,285,216 km2) in area in South America, bordered in the north by Ecuador and Colombia, in the south by Chile, south east by Bolivia, by Brazil in the east and by the Pacific Ocean in the west. Peru has one of the most diverse climates, geographical and ecological in the world, from tropical or subtropical dessert to glacial in highland mountains to Amazon jungle. Peru is divided into 24 geopolitical regions with a central government. According to last national census in 2017, Peruvian populations accounts for 31,237,385 inhabitants (Instituto Nacional de Estadistica e Informatica [INEI], 2017). Most of Peru's population lives in the Coastal area, with almost one third of the nation's population living in Lima, the largest city with approximately 11 million people. Rural and urban population has changed over the last 50 years due to migration waves in the 1950s from rural to urban sites mainly located in the coast causing decrease or disappearance of native communities. Revisado por pares

Western South America was one of the worldwide cradles of civilization. The well known Inca Empire was the tip of the iceberg of a cultural and biological evolutionary process that started 14-11 thousand years ago. Genetic data from 18 Peruvian populations reveal that: (1) The between-population homogenization of the central-southern Andes and its differentiation with respect to Amazonian populations of similar latitudes do not extend northward. Instead, longitudinal gene flow between the northern coast of Peru, Andes and Amazonia accompanied cultural and socioeconomic interactions revealed by archeological studies. This pattern recapitulates the environmental and cultural differentiation between the fertile north, where altitudes are lower; and the arid south, where the Andes are higher, acting as a genetic barrier between the sharply different environments of the Andes and Amazonia (2). The genetic homogenization between the populations of the arid Andes is not only due to migration during the Inca Empire or the subsequent colonial period. It started at least during the earlier expansion of the pre-Inca Wari Empire (600-1000 YBP) (3) This demographic history allowed for cases of positive natural selection in the high and arid Andes vs. the low Amazon tropical forest: in the Andes, HAND2-AS1 (heart and neural crest derivatives expressed 2 antisense RNA1, related with cardiovascular function) and DUOX2 (dual oxidase 2, related to thyroid function and innate immunity) genes; in the Amazon, the gene encoding for the CD45 protein, essential for antigen recognition by T/B lymphocytes in viral-host interaction, consistent with the host-virus arms race hypothesis.

Lung cancer is a leading cause of cancer-related death among both men and women in the United States, where non–small cell lung cancer accounts for ∼85% of lung cancer. Lung adenocarcinoma (ADC) is the major histologic subtype. The presence of actionable mutations prompts the use of therapies designed to specifically address the deleterious effects of those cancer-driving mutations; these therapies have already shown promise in cases carrying those actionable mutations (∼30%). Innovative therapeutic approaches are needed for the treatment of 70% of patients suffering from lung ADC. Adoptive transfer of CD8+ T cells specific against cancer/testis (CT) Ags, whose protein expression is restricted to the gonads (testis and ovary) and cancerous cells, is an excellent alternative. In this study, we report the isolation of HLA-A*02:01/CT37 peptide–specific α and β TCR chains from a CD8+ T cell clone obtained from a patient suffering from lung ADC. We also report the development of an innovative CD3ζ construct. With those TCR chains and the engineered (modified) CD3ζ chain, we produced a construct that when transduced into CD8+ T cells is capable of redirecting transduced CD8+ T cell cytotoxic activity and IFN-γ secretion against peptide-pulsed autologous cells and HLA-A*02:01–positive and CT37-expressing lung ADC cell lines. Our findings will launch the development of innovative adoptive transfer immunotherapies for the treatment of lung ADC, targeting the most prevalent HLA molecules and CT37 peptides restricted by these molecules.

SUMMARYGuillain-Barre Syndrome (GBS) is considered a complex disorder with significant environmental effect and genetic susceptibility. Genetic polymorphisms in CD1E, CD1A, IL-17 and/or ICAM-1 genes had been proposed as susceptibility genetic variants for GBS mainly in Caucasian population. This study explores the association between selected polymorphisms in these genes and GBS susceptibility in confirmed GBS cases reported in mestizo population from northern Peru during the most recent GBS outbreak of May 2018. A total of 9 non-related cases and 11 controls were sequenced for the polymorphic regions of CD1A, CD1E, IL-17 and ICAM-1 genes. We found a significant protective association between heterozygous GA genotype in ICAM-1 gene (241Gly / Arg) and GBS (p IL-17 was monomorphic in both controls and patients. No significant differences were found in the frequency of SNPs in CD1A and CD1E between the group with GBS patients and healthy controls. Further studies with larger sample size will be required to validate these findings.

The Transatlantic Slave Trade transported more than 9 million Africans to the Americas between the early 16th and the mid-19th centuries. We performed genome-wide analysis of 6,267 individuals from 22 populations and observed an enrichment in West-African ancestry in northern latitudes of the Americas, whereas South/East African ancestry is more prevalent in southern South-America. This pattern results from distinct geographic and geopolitical factors leading to population differentiation. However, we observed a decrease of 68% in the African gene pool between-population diversity within the Americas when compared to the regions of origin from Africa, underscoring the importance of historical factors favoring admixture between individuals with different African origins in the New World. This is consistent with the excess of West-Central Africa ancestry (the most prevalent in the Americas) in the US and Southeast-Brazil, respect to historical-demography expectations. Also, in most of the Americas, admixture intensification occurred between 1,750 and 1,850, which correlates strongly with the peak of arrivals from Africa. This study contributes with a population genetics perspective to the ongoing social, cultural and political debate regarding ancestry, race, and admixture in the Americas.Significance StatementDifferently from most genetic studies, that have estimated the overall African ancestry in the Americas, we perform a finer geographic analysis and infer how different African groups contributed to North-, South-American and Caribbean populations, in the context of geographic and geopolitical factors. We also perform a formal comparison of information from demographic history records of the Transatlantic Slave Trade with inferences based on genomic diversity of current populations. Our approach reveals the distinct regional African ancestry roots of different populations from North-, South-America and the Caribe and other important aspects of the historical process of mestizaje and its dynamics in the American continent.

To analyze the differential expression of miR-21, miR-29a, miR-99b and miR-155 in serum samples from patients with latent tuberculosis (TB) and active TB compared to healthy controls.We used 28 serum samples (9 with active TB, 10 with latent TB and 9 healthy con trols) for the analysis of gene expression by RT-qPCR with Primers and TaqMan probes. The differential expression was calculated by the Livak method using a normalizing gene (RNU-48).Overex pression of miR-155 was found in people with latent tuberculosis, compared to healthy controls (0.63 vs. 0.01; p value = 0.032).The miR-155 could be considered a biomarker to differentiate latent TB from active disease. Studies with larger sample sizes are required to corroborate the findings.El objetivo del estudio fue analizar la expresión diferencial de miR-21, miR-29a, miR-99b y miR-155 en muestras de suero de pacientes con tuberculosis (TB) latente y TB activa respecto a contro les sanos.Se utilizaron 28 muestras de suero (nueve con TB activa, diez con TB latente y nueve controles sanos) para el análisis de expresión génica mediante RT-qPCR con Primers y sondas TaqMan. Se calculó la expresión diferencial por el método de Livak utilizando un gen norma lizador (RNU-48).Se halló una sobreexpresión de miR-155 en personas con tuberculosis latente, respecto a los controles sanos (0,63 vs. 0,01; valor de p=0,032).El miR-155 podría ser considerado un biomarcador para diferenciar TB latente de enfermedad activa. Se requieren estudios con mayores tamaños muestrales para corroborar nuestros hallazgos.

On average, Peruvian individuals are among the shortest in the world1. Here we show that Native American ancestry is associated with reduced height in an ethnically diverse group of Peruvian individuals, and identify a population-specific, missense variant in the FBN1 gene (E1297G) that is significantly associated with lower height. Each copy of the minor allele (frequency of 4.7%) reduces height by 2.2 cm (4.4 cm in homozygous individuals). To our knowledge, this is the largest effect size known for a common height-associated variant. FBN1 encodes the extracellular matrix protein fibrillin 1, which is a major structural component of microfibrils. We observed less densely packed fibrillin-1-rich microfibrils with irregular edges in the skin of individuals who were homozygous for G1297 compared with individuals who were homozygous for E1297. Moreover, we show that the E1297G locus is under positive selection in non-African populations, and that the E1297 variant shows subtle evidence of positive selection specifically within the Peruvian population. This variant is also significantly more frequent in coastal Peruvian populations than in populations from the Andes or the Amazon, which suggests that short stature might be the result of adaptation to factors that are associated with the coastal environment in Peru. In an ethnically diverse group of Peruvian individuals, the population-specific, missense variant in FBN1 (E1297G) is associated with lower height and shows evidence of positive selection within the Peruvian population.

Tuberculosis is a health problem worldwide with one-third of the population infected with the Mycobacterium tuberculosis bacilli. The first-line of treatment for tuberculosis includes the drugs Isoniazid (INH) and Rifampicin (RIF) metabolized in the liver. Drug metabolism is directly related to the genetic variation of NAT2 and CYP2E1 (associated with INH metabolism) and AADAC (associated with RIF metabolism), and the effects produced in an individual may be a fast, intermediate or slow metobolizer. Polymorphisms in genes of people in standard tuberculosis treatment can cause effects on drug metabolism with consequences of hepatotoxicity and even drug resistance. Countries have began clinical trials focusedon personalization of tuberculosis treatment to reduce the consequences for patients in treatment. In countries like Peru, where high rates of tuberculosis are recorded and therefore more people in treatment, the pharmacogenomic of individuals becomes a crucial tool for an optimum tuberculosis treatment. This review highlights the importance of having pharmacogenomic studies and having the identification of polymorphisms associated to the metabolism of theanti-tuberculosis drugs in our Peruvian population. La tuberculosis es un problema de salud Pública a nivel mundial con un tercio de la población infectada por el bacilo Mycobacterium tuberculosis. El tratamiento de primera línea incluye a las drogas isoniazida (INH) y rifampicina (RIF) metabolizadas en el hígado. La metabolización de drogas está directamente relacionada con la variación genética de NAT2 y CYP2E1 (asociados a metabolismo de INH) y AADAC (asociados a metabolismo de RIF), y los efectos pueden producir que un individuo sea metabolizador rápido, intermedio o lento. Los polimorfismos en genes de personas con tratamiento estándar de tuberculosis pueden ocasionar efectos en el metabolismo de drogas con consecuencias de hepatoxicidad e, incluso, posible drogorresistencia. Algunos países han empezado ensayos clínicos enfocados en la personalización del tratamiento a tuberculosis para reducir las consecuencias en pacientes en tratamiento. En países como el Perú, donde se registran altos índices de tuberculosis y, por consiguiente, más población en tratamiento, la farmacogenómica de individuos se convierte en una herramienta crucial para un óptimo tratamiento. La presente revisión destaca la importancia de tener estudios en farmacogenómica e identificar los polimorfismos asociados al metabolismo de las drogas antituberculosas en nuestra población peruana.

Significance Through the Peruvian Genome Project we generate and analyze the genomes of 280 individuals where the majority have >90% Native American ancestry and explore questions at the interface of evolutionary genetics, history, anthropology, and medicine. This is the most extensive sampling of high-coverage Native American and mestizo whole genomes to date. We estimate an initial peopling of Peru was rapid and began by 12,000 y ago. In addition, the mestizo populations exhibit admixture between Native American groups prior to their Spanish admixture and was likely influenced by the Inca Empire and Spanish conquest. Our results address important Native American population history questions and establish a dataset beneficial to address the underrepresentation of Native American ancestry in sequencing studies., Native Americans from the Amazon, Andes, and coastal geographic regions of South America have a rich cultural heritage but are genetically understudied, therefore leading to gaps in our knowledge of their genomic architecture and demographic history. In this study, we sequence 150 genomes to high coverage combined with an additional 130 genotype array samples from Native American and mestizo populations in Peru. The majority of our samples possess greater than 90% Native American ancestry, which makes this the most extensive Native American sequencing project to date. Demographic modeling reveals that the peopling of Peru began ∼12,000 y ago, consistent with the hypothesis of the rapid peopling of the Americas and Peruvian archeological data. We find that the Native American populations possess distinct ancestral divisions, whereas the mestizo groups were admixtures of multiple Native American communities that occurred before and during the Inca Empire and Spanish rule. In addition, the mestizo communities also show Spanish introgression largely following Peruvian Independence, nearly 300 y after Spain conquered Peru. Further, we estimate migration events between Peruvian populations from all three geographic regions with the majority of between-region migration moving from the high Andes to the low-altitude Amazon and coast. As such, we present a detailed model of the evolutionary dynamics which impacted the genomes of modern-day Peruvians and a Native American ancestry dataset that will serve as a beneficial resource to addressing the underrepresentation of Native American ancestry in sequencing studies.

To analyze melting curves for the diagnosis of multidrug-resistant tuberculosis from sputum samples.Sputum samples (n = 250) were collected from patients with clinical suspicion of pulmonary tuberculosis as a result of bacilloscopy and cultured in solid medium Lowenstein Jensen. According to the reference method, 124 samples sensitive to rifampicin and isoniazid, 24 resistant to rifampicin, 33 resistant to isoniazid, and 69 multidrug-resistant were used. It was evaluated by real-time PCR and then by melting curves, the rpoB gene was used as a biomarker of rifampicin resistance, and the katG gene and inhA promoter region were used as biomarkers of isoniazid resistance. The H37Rv strain was considered a drug-sensitive control. The results of the reference method and the results of the melting curve analysis were compared to evaluate the parameters of sensitivity, specificity, positive predictive value and negative predictive value.Rifampicin resistance showed a sensitivity of 90.3%, specificity of 90.4%, positive predictive value of 84.8% and negative predictive value of 94.0%. Isoniazid resistance showed a sensitivity of 90.2%, specificity of 93.9%, positive predictive value of 91.1% and negative predictive value of 93.3%. The detection of multidrug-resistant tuberculosis showed values of 89.9%, 90.6%, 78.5% and 95.9% for sensitivity, specificity, positive predictive value and negative predictive value, respectively.The melting curve analysis showed to be safe and reliable to be used in the rapid diagnosis of multidrug-resistant tuberculosis in sputum samples.Analizar curvas de melting para el diagnóstico de tuberculosis multidrogorresistente a partir de muestras de esputo.Se colectaron muestras de esputo (n = 250) de pacientes con sospecha clínica de tuberculosis pulmonar según resultado de baciloscopia y cultivados en medio sólido Lowenstein Jensen. Según el método de referencia se trabajó con 124 muestras sensibles a rifampicina e isoniacida, 24 resistentes a rifampicina, 33 resistentes a isoniacida y 69 multidrogorresistentes. Se evaluó por PCR en tiempo real y luego por las curvas de melting, se utilizó el gen rpoB como biomarcador de resistencia a rifampicina, y el gen katG y región promotora inhA como biomarcadores de resistencia a isoniacida. La cepa H37Rv fue considerada como control sensible a drogas. Se compararon los resultados del método de referencia y los resultados del análisis de curvas de melting para evaluar los parámetros de sensibilidad, especificidad, valor predictivo positivo y valor predictivo negativo.La resistencia a rifampicina mostró una sensibilidad de 90,3 %, especificidad de 90,4 %, valor predictivo positivo de 84,8 % y valor predictivo negativo de 94,0 %. La resistencia a isoniacida mostró una sensibilidad de 90,2 %, especificidad de 93,9 %, valor predictivo positivo de 91,1 % y valor predictivo negativo de 93,3 %. La detección de tuberculosis multidrogorresistente mostró valores de 89,9 %, 90,6 %, 78,5 % y 95,9 % para sensibilidad, especificidad, valor predictivo positivo y valor predictivo negativo, respectivamente.El análisis de curvas de melting mostró ser seguro y confiable para ser utilizado en el diagnóstico rápido de tuberculosis multidrogorresistente en muestras de esputo.

BackgroundEarly detection and diagnosis of tuberculosis remain major global priorities for tuberculosis control. Few studies have used a qualitative approach to investigate the social determinants contributing to diagnostic delay and none have compared data collected from individual, community, and health-system levels. We aimed to characterize the social determinants that contribute to diagnostic delay among persons diagnosed with tuberculosis living in resource-constrained settings.Methods/principle findingsData were collected in public health facilities with high tuberculosis incidence in 19 districts of Lima, Peru. Semi-structured interviews with persons diagnosed with tuberculosis (n = 105) and their family members (n = 63) explored health-seeking behaviours, community perceptions of tuberculosis and socio-demographic circumstances. Focus groups (n = 6) were conducted with health personnel (n = 35) working in the National Tuberculosis Program. All interview data were transcribed and analysed using a grounded theory approach. The median delay between symptom onset and the public health facility visit that led to the first positive diagnostic sample was 57 days (interquartile range 28-126). The great majority of persons diagnosed with tuberculosis distrusted the public health system and sought care at public health facilities only after exhausting other options. It was universally agreed that persons diagnosed with tuberculosis faced discrimination by public and health personnel. Self-medication with medicines bought at local pharmacies was reported as the most common initial health-seeking behaviour due to the speed and low-cost of treatment in pharmacies. Most persons diagnosed with tuberculosis initially perceived their illness as a simple virus.ConclusionsDiagnostic delay was common and prolonged. When individuals reached a threshold of symptom severity, they addressed their health with the least time-consuming, most economically feasible, and well-known healthcare option available to them. In high-burden settings, more human and material resources are required to promote tuberculosis case-finding initiatives, reduce tuberculosis associated stigma and address the social determinants underlying diagnostic delay.

BackgroundThe metabolic conversion of dietary omega-3 and omega-6 18 carbon (18C) to long chain (> 20 carbon) polyunsaturated fatty acids (LC-PUFAs) is vital for human life. Fatty acid desaturase (FADS) 1 and 2 catalyze the rate-limiting steps in the biosynthesis of LC-PUFAs. TheFADSregion contains two haplotypes; ancestral and derived, where the derived haplotypes are associated with more efficient LC-PUFA biosynthesis and is nearly fixed in Africa. In addition, Native American populations appear to be nearly fixed for the lesser efficient ancestral haplotype, which could be a public health problem due to associated low LC-PUFA levels, while Eurasia is polymorphic. This haplotype frequency distribution is suggestive of archaic re-introduction of the ancestral haplotype to non-African populations or ancient polymorphism with differential selection patterns across the globe. Therefore, we tested theFADSregion for archaic introgression or ancient polymorphism. We specifically addressed the genetic architecture of theFADSregion in Native American populations to better understand this potential public health impact.ResultsWe confirmed Native American ancestry is nearly fixed for the ancestral haplotype and is under positive selection. The ancestral haplotype frequency is also correlated to Siberian populations’ geographic location further suggesting the ancestral haplotype’ s role in cold weather adaptation and leading to the high haplotype frequency within Native American populations’. We also find that the Neanderthal is more closely related to the derived haplotypes while the Denisovan clusters closer to the ancestral haplotypes. In addition, the derived haplotypes have a time to the most recent common ancestor of 688,474 years ago which is within the range of the modern-archaic hominin divergence.ConclusionsThese results support an ancient polymorphism forming in theFADSgene region with differential selection pressures acting on the derived and ancestral haplotypes due to the old age of the derived haplotypes and the ancestral haplotype being under positive selection in Native American ancestry populations. Further, the near fixation of the less efficient ancestral haplotype in Native American ancestry suggests the need for future studies to explore the potential health risk of associated low LC-PUFA levels in Native American ancestry populations.

Background The emergence of multidrug-resistant strains is a major health problem especially for countries with high TB incidence such as Peru. In this study, we evaluated High Resolution Melting (HRM) assay in Peruvian isolates for the detection of mutations within rpoB, katG genes and promoter region inhA to determine isoniazid and rifampicin resistance in Mycobacterium tuberculosis (Mtb). Methods DNA samples extracted from a total of 167 clinical isolates of Mtb, 89 drug-sensitive and 78 multidrug-resistant, were blindly analyzed by HRM analysis and verified by DNA sequencing. Results The HRM analysis generated patterns that were specific to distinguish between sensitive and resistance isolates. The sensitivity and specificity of the HRM assays in comparison with drug susceptibility testing (DST) for detection of rifampicin resistance were 98.7 % and 97.5 %, and for isoniazid resistance were 98.7 % and 100 %. Conclusion This study suggests that HRM Analysis could help with rapid diagnosis of MDR-TB cases in Peru.

We are reporting that the two-locus genotype -2518 macrophage chemoattractant protein (MCP)-1 GG and -1607 matrix metalloproteinase (MMP)-1 2G/2G promotes the expression of hyperinflammation in response to Mycobacterium tuberculosis infection, inducing extensive tissue damage and severe tuberculosis (TB) disease. Carriers of this two-locus genotype have a 13-fold higher chance of developing severe disease and 6.5-fold higher chance of developing permanent lesions, and a 3.864-fold higher chance of delayed response to first-line standardized treatment than carriers of any other relevant combination of genotypes at those two loci. Thus, these persons have an increased likelihood of poor health-related quality of life and of transmitting M. tuberculosis to other members of the community. In addition, through the analysis of human lung tissues, serum/plasma and in vitro experiments, including in vitro infections of THP-1 cells with M. tuberculosis and microarray analysis, we determined that this hyperinflammation state is potentially driven by the MCP-1/MMP-1/PAR-1 pathway. Hence, we are providing markers for the identification of TB cases that may develop severe pulmonary disease and delayed response to treatment, and are providing the basis for development of novel host-targeted clinical interventions to ameliorate the severity of pulmonary TB.

Latent tuberculosis infection (LTBI) is defined as an infection with Mycobacterium tuberculosis (MTB) without clinical, bacteriological, or radiological findings, and its early diagnosis is essential for eradication of tuberculosis. To identify LTBI, we measured the numbers of interferon-gamma producing T cells, based on the ELISPOT assay, and the antibody titers in the sera to tuberculous glycolipid antigen (TBGL-Ab). Seventeen culture-confirmed TB patients, 13 controls from TB endemic areas (EC) and 13 controls from TB non-endemic areas (NEC) were enrolled. Peripheral blood mononuclear cells (2.5 x 10(5) per well) were cultured on plates precoated with antibody against interferon-gamma. ELISPOT response was defined as positive when the MTB-specific antigen-containing wells showed at least 6 spots and twice numbers of spots than negative control wells. ELISPOT responses were positive in 15 (88%), 8 (62%) and 4 (31%) subjects of TB, EC and NEC groups, respectively. The ELISPOT data differ between TB and NEC groups (p0.01) but not between TB and EC groups. In contrast, TBGL-Ab titers were elevated (2.0 U/ml) in 12 TB patients (71%), but only in one subject (8%) each from EC and NEC groups. These results indicate the high prevalence of LTBI in EC. In conclusion, LTBI is associated with positive ELISPOT assay and the low titer of TBGL-Ab, while positive results both in ELISPOT and TBGL-Ab assays indicate active TB. The low titer of TBGL-Ab is a helpful marker to identify LTBI in ELISPOT-positive individuals in TB endemic areas.

In 43 MAC infected patients (23 non-HIV and 20 AIDS) the IgG response against 3 BCG and 2 MAC antigens was assessed. The response to four antigens in patients with AIDS was considerably lower than in non-HIV infected patients. Therefore, antibody production against MAC glycolipid antigens was impaired in AIDS patients.

We analyzed whole genome–based transcriptional profiles of Mycobacterium tuberculosis subjected to prolonged hypoxia to guide the discovery of novel potential Ags, by a combined bioinformatic and empirical approach. We analyzed the fold induction of the 100 most highly induced genes at 7 d of hypoxia, as well as transcript abundance, peptide-binding prediction (ProPred) adjusted for population-specific MHC class II allele frequency, and by literature search. Twenty-six candidate genes were selected by this bioinformatic approach and evaluated empirically using IFN-γ and IL-2 ELISPOT using immunodominant Ags (Acr-1, CFP-10, ESAT-6) as references. Twenty-three of twenty-six proteins induced an IFN-γ response in PBMCs of persons with active or latent tuberculosis. Five novel immunodominant proteins—Rv1957, Rv1954c, Rv1955, Rv2022c, and Rv1471—were identified that induced responses similar to CFP-10 and ESAT-6 in both magnitude and frequency. IL-2 responses were of lower magnitude than were those of IFN-γ. Only moderate evidence of infection stage–specific recognition of Ags was observed. Reconciliation of bioinformatic and empirical hierarchies of immunodominance revealed that Ags could be predicted, providing transcriptomic data were combined with peptide-binding prediction adjusted by population-specific MHC class II allele frequency.

M. tuberculosis (MTB) species-specific antigenic determinants of the human T cell response are important for immunodiagnosis and vaccination. As hypoxia is a stimulus in chronic tuberculosis infection, we analyzed transcriptional profiles of MTB subject to 168 hours of hypoxia to test the hypothesis that upregulation by hypoxia might result in gene products being recognized as antigens. We identified upregulation of two region of difference (RD) 11 (Rv2658C and Rv2659c), and one RD2 (Rv1986) absent from commonly used BCG strains. In MTB infected persons, the IL-2 ELISpot response to Rv1986 peptides was several times greater than the corresponding IFN-γ response to the reference immunodominant ESAT-6 or CFP-10 antigens. The IL-2 response was confined to two epitopic regions containing residues 61–80 and 161–180. The biggest population of IL-2 secreting T cells was single cytokine positive central memory T cells. The IL-2 response to live MTB bacilli lacking Rv1986 was significantly lower than the response to wild type or mutant complemented with Rv1986. In addition, the IL-2 response to Rv1986 was significantly lower in HIV-TB co-infected persons than in HIV uninfected persons, and significantly increased during antiretroviral therapy. These findings demonstrate that Rv1986 is an immunodominant target of memory T cells and is therefore of relevance when considering the partial efficacy of currently used BCG vaccines and provide evidence for a clinical trial comparing BCG strains., Author Summary Mycobacterium tuberculosis (the cause of tuberculosis) can persist for many years in humans without causing disease but has the potential to reactivate. One of the conditions the bacterium must survive in these circumstances is hypoxia. In order to do so, the bacterium uses a characteristic set of genes that help alter its metabolism. It follows that the products of such genes may encode protein antigens that can be recognized by the immune response. We therefore analyzed gene response patterns of tuberculosis subject to prolonged hypoxia as a guide to the discovery of new antigens that might be useful as vaccines or diagnostic agents. Amongst the genes most strongly increased by low oxygen levels, one was identified (known as Rv1986) that is missing from most strains of the tuberculosis vaccine Mycobacterium bovis BCG. When we analyzed human immune responses to this protein in tuberculosis infected people our experiments showed it was particularly well recognized by cells that produce a chemical messenger (cytokine) called interleukin-2. Interleukin-2 is important for long-term immunological memory. The BCG vaccine is only partially effective and our experiments therefore suggest one of the reasons could be that an important immunological target is missing from many strains. Further evaluation of BCG strains in which Rv1986 is present or absent is therefore warranted in the hope that this might improve the efficacy of existing or new tuberculosis vaccines.

Based on the tuberculin skin test it is estimated that latent tuberculosis infection is present in one-third of the world's population. The new strategies in public health and research are aimed to reduce and eradicate this enormous reservoir. However, the absence of effective biomarkers for diagnosis and treatment of latent tuberculosis limits the development of new drugs and vaccines. Some components are present in both, the PPD (used in the tuberculin skin test) and the BCG vaccine. This increases the number of false positives in vaccinated individuals. Nowadays, there is not an immune diagnostic method that can differentiate latent tuberculosis and tuberculosis disease. New studies have addressed some strategies including specific antibodies, new cytokines and / or antigens as candidates for biomarkers. However, the high costs of these studies, the low number of participants and their different methodology make difficult a future meta-analysis and more conclusive results.

A nationwide study was undertaken to determine the susceptibility to penicillin and serotypes of Streptococcus pneumoniae in Japan. S. pneumoniae was isolated from 114 adult patients with community-acquired pneumonia over 22 months at 20 hospitals and medical centres in different regions in Japan. All but five isolates were from sputum. Forty-eight isolates (42·1%) were susceptible, 40 (35·1%) showed intermediate resistance (MIC, 0·12–1·0 μg/ml) and 26 (22·8%) were resistant (MIC, [ges ]2·0 μg/ml) to penicillin G. All isolates were susceptible to ceftriaxone (breakpoint 1 μg/ml), imipenem (4 μg/ml) and vancomycin (4 μg/ml). Most were resistant to erythromycin, clarithromycin and azithromycin; only two were resistant to levofloxacin. Differences were found in the distribution of serotypes among isolates showing susceptibility to penicillin (predominant types 3, 6B, and 19F), intermediate resistance (6B, 14, 19F, and 23F) and full resistance (19F and 23F). PFGE typing showed that 14 of the 25 strains of serotype 19F had a single DNA profile, pattern A, a pattern closely similar to that of the Taiwan multidrug-resistant 19F clone. Twelve pattern A strains were not susceptible to penicillin but carried the macrolide resistance gene mef(A). The DNA profiles of the 15 strains of 23F were also heterogeneous but six were highly similar (pattern b) yet distinct from the Spanish multidrug-resistant 23F clone although possibly related to the Taiwan multidrug-resistant 23F clone. The pattern b strains were not susceptible to penicillin and also harboured either mef(A) or erm(B). Our results indicate that multidrug-resistant pneumococci are spreading rapidly in Japan. Efforts to prevent the spread of the pandemic multidrug-resistant serotypes should be intensified.

The possible intrafamiliar transmission of Moraxella catarrhalis was evaluated in 3 pairs between children and their parents, and 8 pairs between siblings from 11 families. Of the 22 isolates, all were found producing beta-lactamase. Molecular typing by pulsed-field gel electrophoresis (PFGE) with Not I and Spe I showed that the PFGE patterns in 2 of 3 pairs between children and their parents, and 4 of 8 pairs between siblings were indistinguishable and those of the remaining pairs were different. These data indicate a possible high rate of intrafamiliar transmission of M. catarrhalis.

The polymerase chain reaction (PCR) is a highly sensitive method for the detection of Mycobacterium tuberculosis and is available in most countries, though to a lesser extent in rural areas.To amplify M. tuberculosis DNA sequences of sputum spotted on FTA cards and compare them with the results of microscopic examination among culture-positive samples.A total of 102 sputum specimens of TB patients in treatment were spotted on FTA cards and stored at room temperature until DNA analysis. We assessed the IS6110 region of M. tuberculosis. The efficacy of the PCR assay for the direct detection of M. tuberculosis was evaluated and compared with the results of cultures (Middlebrook 7H9 broth) and smears of fresh sputum specimens.We were able to detect 10 fg/microl of mycobacterial DNA even after 6 months in storage. The PCR sensitivity and specificity using the FTA card system were 82% and 96%, while microscopic examination showed 41% and 95%, respectively.The FTA card system for the storage of bacterial DNA from sputum samples should be considered for the molecular diagnosis of tuberculosis. Samples can easily be obtained from geographically isolated populations and shipped by mail for accurate molecular diagnosis.

To evaluate differences in anti-tuberculous glycolipid (TBGL) antibody titers in patients who developed tuberculosis (TB) with and without gastrectomy, 11 gastrectomised patients who developed TB after surgery (GS-TB), 19 TB patients without any other complications (TB), 12 gastrectomised patients who did not develop TB after surgery (GS) and 27 healthy subjects (H) with normal findings on chest X-ray were evaluated, although there were no differences in the clinical findings at admission between the TB and GS-TB groups. The assay used here allowed us to find low anti-TBGL antibody titers in GS-TB patients.