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Novel or rare damaging mutations have been implicated in the developmental pathogenesis of nonsyndromic cleft lip with or without cleft palate (nsCL ± P). Thus, we investigated the human genome for high-impact mutations that could explain the risk of nsCL ± P in our cohorts.We conducted next-generation sequencing (NGS) analysis of 130 nsCL ± P case-parent African trios to identify pathogenic variants that contribute to the risk of clefting. We replicated this analysis using whole-exome sequence data from a Brazilian nsCL ± P cohort. Computational analyses were then used to predict the mechanism by which these variants could result in increased risks for nsCL ± P.We discovered damaging mutations within theThis is the first report on the contribution of

The majority (85%) of nonsyndromic cleft lip with or without cleft palate (nsCL/P) cases occur sporadically, suggesting a role for de novo mutations (DNMs) in the etiology of nsCL/P. To identify high impact DNMs that contribute to the risk of nsCL/P, we conducted whole genome sequencing (WGS) analyses in 130 African case-parent trios (affected probands and unaffected parents). We identified 162 high confidence protein-altering DNMs that contribute to the risk of nsCL/P. These include novel loss-of-function DNMs in the ACTL6A, ARHGAP10, MINK1, TMEM5 and TTN genes; as well as missense variants in ACAN, DHRS3, DLX6, EPHB2, FKBP10, KMT2D, RECQL4, SEMA3C, SEMA4D, SHH, TP63, and TULP4. Experimental evidence showed that ACAN, DHRS3, DLX6, EPHB2, FKBP10, KMT2D, MINK1, RECQL4, SEMA3C, SEMA4D, SHH, TP63, and TTN genes contribute to facial development and mutations in these genes could contribute to CL/P. Association studies have identified TULP4 as a potential cleft candidate gene, while ARHGAP10 interacts with CTNNB1 to control WNT signaling. DLX6, EPHB2, SEMA3C and SEMA4D harbor novel damaging DNMs that may affect their role in neural crest migration and palatal development. This discovery of pathogenic DNMs also confirms the power of WGS analysis of trios in the discovery of potential pathogenic variants.

Novel or rare damaging mutations have been implicated in the developmental pathogenesis of nonsyndromic cleft lip with or without cleft palate (nsCL ± P). Thus, we investigated the human genome for high-impact mutations that could explain the risk of nsCL ± P in our cohorts. We conducted next-generation sequencing (NGS) analysis of 130 nsCL ± P case-parent African trios to identify pathogenic variants that contribute to the risk of clefting. We replicated this analysis using whole-exome sequence data from a Brazilian nsCL ± P cohort. Computational analyses were then used to predict the mechanism by which these variants could result in increased risks for nsCL ± P. We discovered damaging mutations within the AFDN gene, a cell adhesion molecule (CAMs) that was previously shown to contribute to cleft palate in mice. These mutations include p.Met1164Ile, p.Thr453Asn, p.Pro1638Ala, p.Arg669Gln, p.Ala1717Val, and p.Arg1596His. We also discovered a novel splicing p.Leu1588Leu mutation in this protein. Computational analysis suggests that these amino acid changes affect the interactions with other cleft-associated genes including nectins (PVRL1, PVRL2, PVRL3, and PVRL4) CDH1, CTNNA1, and CTNND1. This is the first report on the contribution of AFDN to the risk for nsCL ± P in humans. AFDN encodes AFADIN, an important CAM that forms calcium-independent complexes with nectins 1 and 4 (encoded by the genes PVRL1 and PVRL4). This discovery shows the power of NGS analysis of multiethnic cleft samples in combination with a computational approach in the understanding of the pathogenesis of nsCL ± P.

Objective Nonsyndromic cleft lip and/or cleft palate (NSCL/P) have multifactorial etiology where genetic factors, gene–environment interactions, stochastic factors, gene–gene interactions, and parent-of-origin effects (POEs) play cardinal roles. POEs arise when the parental origin of alleles differentially impacts the phenotype of the offspring. The aim of this study was to identify POEs that can increase risk for NSCL/P in humans using a genome-wide dataset. Methods The samples (174 case-parent trios from Ghana, Ethiopia, and Nigeria) included in this study were from the African only genome wide association studies (GWAS) that was published in 2019. Genotyping of individual DNA using over 2 million multiethnic and African ancestry-specific single-nucleotide polymorphisms from the Illumina Multi-Ethnic Genotyping Array v2 15070954 A2 (genome build GRCh37/hg19) was done at the Center for Inherited Diseases Research. After quality control checks, PLINK was employed to carry out POE analysis employing the pooled subphenotypes of NSCL/P. Results We observed possible hints of POEs at a cluster of genes at a 1 mega base pair window at the major histocompatibility complex class 1 locus on chromosome 6, as well as at other loci encompassing candidate genes such as ASB18, ANKEF1, AGAP1, GABRD, HHAT, CCT7, DNMT3A, EPHA7, FOXO3, lncRNAs, microRNA, antisense RNAs, ZNRD1, ZFAT, and ZBTB16. Conclusion Findings from our study suggest that some loci may increase the risk for NSCL/P through POEs. Additional studies are required to confirm these suggestive loci in NSCL/P etiology.

Objectives Cleft lip with/without cleft palate and cleft palate only are congenital birth defects where the upper lip and/or palate fail to fuse properly during embryonic facial development. Affecting ~1.2/1000 live births world-wide, these orofacial clefts impose significant social and financial burdens on affected individuals and their families. Orofacial clefts have a complex etiology resulting from genetic variants combined with environmental covariates. Recent genome-wide association studies and whole-exome sequencing for orofacial clefts identified significant genetic associations and variants in several genes. Of these, we investigated the role of common/rare variants in SHH, RORA, MRPL53, ACVR1, and GDF11. Materials and methods We sequenced these five genes in 1255 multi-ethnic cleft lip with/without palate and cleft palate only samples in order to find variants that may provide potential explanations for the missing heritability of orofacial clefts. Rare and novel variants were further analyzed using in-silico predictive tools. Results 19 total variants of interest were found, with variant types including stop-gain, missense, synonymous, intronic, and splice-site variants. Of these, 3 novel missense variants were found, one in SHH, one in RORA, and one in GDF11. Conclusion This study provides evidence that variants in SHH, RORA, MRPL53, ACVR1, and GDF11 may contribute to risk of orofacial clefts in various populations.

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Background Early childhood caries (ECC) is a rapidly progressing form of dental infection and a significant public health problem, especially among socially and economically disadvantaged populations. This study aimed to assess the risk factors for ECC among a cohort of Sub-Saharan African children and to determine the role of genetics in the etiology of ECC. Methods A sample of 691 children (338 with ECC, 353 without ECC, age Results Of the 338 children with ECC, 64 (18.9%) had Severe-Early Childhood Caries (S-ECC). Children aged 48–59 months comprised the highest proportion of subjects with ECC (165; 48.8%) and S-ECC (24; 37.5%) while female subjects had higher dt (3.13 ± 2.56) and dmft values 3.27 ± 2.64. ECC was significantly more prevalent among children who were breastfed at night ≥ 12 months (OR 3.30; CI 0.39, 4.75), those with no previous dental visit (OR 1.71; CI 0.24, 2.77), those who used sweetened pacifiers (OR 1.85; CI 0.91, 3.79) and those who daily consumed sugar-sweetened drinks/snacks (OR 1.35; CI 0.09, 18.51). A suggestive increased risk for ECC (OR 1.26, p = 0. 0.0397) was observed for the genetic variant rs11239282 on chromosome 10. We also observed a suggestive reduced risk for ECC (OR 0.80, p = 0.03) for the rs131777 on chromosome 22. None of the genetic variants were significant after correction for multiple testing (Bonferroni p value p = 0.004). Conclusions Prolonged night-time breastfeeding, poor utilization of dental services and daily consumption of sugar were risk factors for ECC. Larger sample size is needed to confirm the results of the genetic analysis and to conduct genome wide studies in order to discover new risk loci for ECC.

Introduction L’atteinte renale au cours des vascularites a ANCA est frequente et severe. La nouvelle classification histo-pathologique de Berden etablie en 2010 permet de classer les glomerulonephrites associees aux ANCA (GAA) en formes focale, mixte, cellulaire et sclereuse. Methodes Le but de ce travail etait d’appliquer cette classification et de demontrer son interet pronostique. Il s’agissait d’une etude retrospective, descriptive et analytique des GAA sur une periode de 10 ans [2007–2017]. Resultats obtenus ou attendus La population etudiee a comportait 17 femmes et 13 hommes âges en moyenne de 54,2 ± 15,7 ans [17–80 ans]. La presentation syndromique etait une glomerulonephrite rapidement progressive dans 90 % des cas avec hematurie et proteinurie dans respectivement 97 % des cas, une reduction de la diurese et des œdemes dans 40 % des cas et une HTA dans 35 % des cas. L’insuffisance renale etait presente dans tous les cas. Les 30 biopsies renales ont ete reclassees selon la classification de Berden en forme focale, mixte et a croissants dans respectivement 7 %, 30 % et 23 % des cas. La forme sclereuse etait retenue dans 40 % des cas. L’evolution etait marquee par une remission complete et partielle dans respectivement 20 % et 37 % des cas, une rechute dans 13 % des cas et un echec therapeutique dans 23 % des cas. Une IRC terminale a ete retenue chez 11 malades (37 %). La forme non sclereuse etait liee a la presence d’œdemes (p : 0,01) et a une mortalite eleve (p : 0,03). La survie etait plus elevee dans la forme a croissants comparativement a la forme mixte et la forme sclereuse (p : 0,03). Conclusion Dans notre population, le diagnostic des GAA se fait a des stades tardifs ; reflete par la predominance de la forme sclereuse. Ce retard diagnostique se traduit par un faible pourcentage de remission et l’importance de l’evolution vers l’IRC terminale.