Microdeletion of the entire IRF6 gene in a Subsaharian African's family with Van der Woude syndrome

Microdeletion of the entire interferon regulatory factory 6 (IRF 6) gene is a rare cause of Van der Woude syndrome (VDW) with only few cases reported in medical literature. Its occurrence in multiple affected members of a family is exceptional. The aim of this presentation was to describe a Central African family with typical VDW phenotype carrying an IRF6 gene deletion. Here we reported phenotype features of members of a Central African family with VDW syndrome consisting of labioalveolar cleft, depressions of the lower lip with labial fistulae (lip pits), submucosal clefts and cleft palate. Mutation analysis by means of multiplex ligation-dependent probe amplification and chromosomal microarray revealed a 374.070 kb, deletion encompassing the entire IRF6 gene in four affected family members. Microdeletion of the entire IRF6 gene causes the classical VDW syndrome phenotype.status: publishe

Microdeletion of the entire IRF6 gene in a Subsaharian African's family with Van der Woude syndrome.

Microdeletion of the entire interferon regulatory factory 6 (IRF 6) gene is a rare cause of Van der Woude syndrome (VDW) with only few cases reported in medical literature. Its occurrence in multiple affected members of a family is exceptional. The aim of this presentation was to describe a Central African family with typical VDW phenotype carrying an IRF6 gene deletion. Here we reported phenotype features of members of a Central African family with VDW syndrome consisting of labioalveolar cleft, depressions of the lower lip with labial fistulae (lip pits), submucosal clefts and cleft palate. Mutation analysis by means of multiplex ligation-dependent probe amplification and chromosomal microarray revealed a 374.070 kb, deletion encompassing the entire IRF6 gene in four affected family members. Microdeletion of the entire IRF6 gene causes the classical VDW syndrome phenotype

Non-syndromic cleft lip and/or cleft palate: Epidemiology and risk factors in Lubumbashi (DR Congo), a case-control study

PURPOSE: To determine the incidence and risk factors of occurrence of non-syndromic cleft lip and/or cleft palate (NSCLP) in Lubumbashi. METHOD: A case-control study was conducted in the health district of Lubumbashi from February 2012 to December 2015. An exhaustive sampling, collecting all newborns with cleft lip and/or cleft palate (CL ± P) in maternity wards was conducted. From a total of 172 cases, 162 non-syndromic cases were recruited. For each case, one clinically normal newborn control was selected. RESULTS: NSCLP had an incidence of 1/1258 live births (0.8/1000). We found significant associations with a family history of cleft lip and palate (CLP) (x2family history = 11.5, p = 0.0007), maternal alcohol intake (OR = 19.3, 95% CI: 1.9-197.1), paternal alcohol during the periconceptional period and the first trimester of pregnancy (OR = 18.7, 95% CI: 3.9-89.2), maternal educational level lower than high school (OR = 9.5, 95% CI: 2.0-44.7), clay (Pemba) consumption during pregnancy (OR = 38.3, 95% CI: 9.3-157.0), the use of insecticides in the evening (OR = 130.3, 95% CI: 13.2-1286.9), indoor cooking with charcoal (Makala) (OR = 6.5, 95% CI: 1.22-34.5), and regular consumption of Kapolowe fish, supposedly contaminated with heavy metals (OR = 29.5, 95% CI: 7.4-116.7). CONCLUSION: Several environmental risk factors highly prevalent in Central Africa for facial clefting were found.status: publishe

High IgG1 Malaria Antibodies Level in Children is a Possible Risk Factor of Blackwater Fever: A Case-Control Study

peer reviewedContext: Pathogenesis of acute massive intravascular hemolysis in Blackwater fever is very complex. Mostly, Malaria immunity deficiency in expatriates, Quinine and Plasmodium are incriminated. The possible role of malaria IgG1 antibodies in BWF is not fully elucidated. Objectives: This study aimed to determine the profile of malaria IgG1 for malaria crude antigen in children developing blackwater fever compared to patients with uncomplicated malaria Methods: This case-control study was conducted in 4 medical institutions across Kinshasa. Cases were patients with Blackwater fever (BWF) whereas controls had uncomplicated Plasmodium falciparum malaria (UM). For each case, 2 controls were recruited and were matched for age, sex and the area of residence. Malaria IgG1 were assessed by standard ELISA and absorbance measured in an automated plate reader. Results: The majority of BWF cases (81.4%) were above 5 years old while only 18.6% were aged below 5 (OR: 1.33; 0.53-3.32). The level of malaria IgG antibodies in BWF children were significantly higher compared to uncomplicated malaria (p=0.002). Quinine was used by 95.3% of the BWF cases ([OR: 50.19 (10.75-234.42)] p<0.001) versus in uncomplicated malaria. There was no linear correlation between the age of patients and the logarithm of antibodies. R2 is totally null (p=0.335). Conclusion: Malaria IgG1 antibodies is significantly elevated in children with BWF and could trigger the occurrence of BWF. The absence of correlation with age suggests that BWF could not be age dependent

Exploring association between MBL2 gene polymorphisms and the occurrence of clinical blackwater fever through a case-control study in Congolese children

BACKGROUND: Blackwater fever (BWF), one of the most severe and life-threatening forms of falciparum malaria, is characterized by acute massive intravascular haemolysis, often leading to acute renal failure. Thus far, the genetics of the underlying susceptibility to develop BWF is not fully elucidated. Deficiency in the MBL protein, an important component of the innate immune system, has previously been suggested to be a susceptibility factor for the development of severe malaria. This study aimed to evaluate the association between MBL2 gene polymorphisms, known to affect the MBL protein level/activity, and the occurrence of BWF among Congolese children. METHODS: This is a case-control study. Cases were patients with BWF, whereas controls, matched for gender and age, had uncomplicated malaria (UM). Dried blood spot was collected for genotyping. RESULTS: A total of 129 children were screened, including 43 BWF and 86 UM. The common allele in BWF and UM was A, with a frequency of 76.7 and 61.0%, respectively (OR: 2.67 (0.87-829) and p = 0.079). The frequency of the C allele was 18.6 and 29.1% in BWF and UM groups, respectively, with p = 0.858. Not a single D allele was encountered. Genotype AA was at higher risk for BWF whereas genotypes A0 (AB and AC) were over-represented in UM group (OR: 0.21 (0.06-0.78)) with p = 0.019. Nine haplotypes were observed in this study: 3 high MBL expression haplotypes and 6 low MBL expression haplotype. One new haplotype HYPC was observed in this study. None of these haplotypes was significantly associated with BWF. CONCLUSION: This pilot study is a preliminary research on MBL2 gene and infectious diseases in DRC. The study results show a higher risk for BWF in AA. This suggests that future studies on BWF should further investigate the contribution of a strong immune response to the occurrence of BWF.status: publishe

Exploring association between MBL2 gene polymorphisms and the occurrence of clinical blackwater fever through a case-control study in Congolese children.

BACKGROUND: Blackwater fever (BWF), one of the most severe and life-threatening forms of falciparum malaria, is characterized by acute massive intravascular haemolysis, often leading to acute renal failure. Thus far, the genetics of the underlying susceptibility to develop BWF is not fully elucidated. Deficiency in the MBL protein, an important component of the innate immune system, has previously been suggested to be a susceptibility factor for the development of severe malaria. This study aimed to evaluate the association between MBL2 gene polymorphisms, known to affect the MBL protein level/activity, and the occurrence of BWF among Congolese children. METHODS: This is a case-control study. Cases were patients with BWF, whereas controls, matched for gender and age, had uncomplicated malaria (UM). Dried blood spot was collected for genotyping. RESULTS: A total of 129 children were screened, including 43 BWF and 86 UM. The common allele in BWF and UM was A, with a frequency of 76.7 and 61.0%, respectively (OR: 2.67 (0.87-829) and p = 0.079). The frequency of the C allele was 18.6 and 29.1% in BWF and UM groups, respectively, with p = 0.858. Not a single D allele was encountered. Genotype AA was at higher risk for BWF whereas genotypes A0 (AB and AC) were over-represented in UM group (OR: 0.21 (0.06-0.78)) with p = 0.019. Nine haplotypes were observed in this study: 3 high MBL expression haplotypes and 6 low MBL expression haplotype. One new haplotype HYPC was observed in this study. None of these haplotypes was significantly associated with BWF. CONCLUSION: This pilot study is a preliminary research on MBL2 gene and infectious diseases in DRC. The study results show a higher risk for BWF in AA. This suggests that future studies on BWF should further investigate the contribution of a strong immune response to the occurrence of BWF

Missense variants in TAF1 and developmental phenotypes: challenges of determining pathogenicity.

We recently described a new neurodevelopmental syndrome (TAF1/MRXS33 intellectual disability syndrome) (MIM# 300966) caused by pathogenic variants involving the X-linked gene TAF1, which participates in RNA polymerase II transcription. The initial study reported eleven families, and the syndrome was defined as presenting early in life with hypotonia, facial dysmorphia, and developmental delay that evolved into intellectual disability (ID) and/or autism spectrum disorder (ASD). We have now identified an additional 27 families through a genotype-first approach. Familial segregation analysis, clinical phenotyping, and bioinformatics were capitalized on to assess potential variant pathogenicity, and molecular modelling was performed for those variants falling within structurally characterized domains of TAF1. A novel phenotypic clustering approach was also applied, in which the phenotypes of affected individuals were classified using 51 standardized Human Phenotype Ontology (HPO) terms. Phenotypes associated with TAF1 variants show considerable pleiotropy and clinical variability, but prominent among previously unreported effects were brain morphological abnormalities, seizures, hearing loss, and heart malformations. Our allelic series broadens the phenotypic spectrum of TAF1/MRXS33 intellectual disability syndrome and the range of TAF1 molecular defects in humans. It also illustrates the challenges for determining the pathogenicity of inherited missense variants, particularly for genes mapping to chromosome X. This article is protected by copyright. All rights reserved