Evaluation d'une technique d'extraction et d'amplification de l'ARN viral Delta à partir des taches de sang et de sérums séchés sur papiers buvards

Date du colloque&nbsp;: 12/2009</p

Identification a novel pathogenic LRTOMT mutation in Mauritanian families with nonsyndromic deafness

International audiencePurposeAlthough recessive mutations in GJB2 are the common genetic etiology of sensorineural hearing impairment (SNHI), variants in LRTOMT gene were also identified, mostly in Middle East and North African populations.MethodsUsing Sanger sequencing we screened the exon 7 of LRTOMT in a cohort of 128 unrelated Mauritanian children with congenital deafness.ResultsOnly one biallelic missense mutation, predicted as pathogenic (c.179 T > C;p.Leu60Pro) was found at homozygous state in four families. This variant, not reported before, showed a deleterious effect by SIFT (score: 0.01) and a disease-causing effect by Mutation Taster (prob: 1). Exploration of the encoded protein 3D structure revealed a disruption from an organized α helix (in the normal protein structure) into a random conformation. Early fitting of a cochlear implant seemed to improve the audition ability of the mutation carrier.ConclusionFurther screening using a panel of deafness genes may expose other variants underlying hearing impairment in our population

Screening of BRCA1/2 variants in Mauritanian breast cancer patients

Abstract Background and study aim Carrying a pathogenic BRCA1/2 variant increases greatly young women’s risk of developing breast cancer (BC). This study aimed to provide the first genetic data on BC in Mauritania. Methods Using NGS based screening; we searched for BRCA1/2 variants in DNA samples from 137 patients diagnosed for hereditary BC. Results We identified 16 pathogenic or likely pathogenic (PV) variants carried by 38 patients. Two predominant BRCA1 PV variants were found: c.815_824dup and c.4986 + 6 T > C in 13 and 7 patients, respectively. Interestingly, three novels BRCA1/2 predicted pathogenic variants have also been detected. Notably, no specific distribution of BRCA1/2 variants was observed regarding triple negative breast cancer (TNBC) or patient gender status. Conclusions In this first genetic profiling of BC in Mauritania, we identified a substantial number of BRCA1/2 pathogenic variants. This finding could be important in the future diagnosis and prevention policy of hereditary BC in Mauritania

Virological and epidemiological features of hepatitis delta infection among blood donors in Nouakchott, Mauritania

International audienceBackgroundIn Mauritania, some authors have described a possible high prevalence of hepatitis delta virus (HDV) infection in the 1990s in studies of small-size samples. Objectives The aims of our study were to assess the prevalence of HDV in HBsAg positive blood donors in Mauritania, to identify the main risk factors for HDV transmission and to analyze genetic diversity of HDV strains. Study design From October 2008 to December 2009, 11,100 consecutive blood donors were considered in this study. Among them, 1700 (15.3%) were HBsAg positive and 455 accepted to participate in this study. Demographic, epidemiological, ethnical, clinical and biological data were recorded. HDV screening, i.e., antibodies (HDVAb) and RNA (HDV-RNA) detection, was performed for all of them as well as HDV and HBV genotyping. Results Ninety/455 (19.78%) donors were HDVAb positive and HDV-RNA was detectable in 56 (62.2%) of them. HDV infection was significantly associated with older age, number of marriages, military profession, residence in the desert and a history of hospitalization. The HDV genotypes of the circulating strains were HDV-1 (89.3%) and HDV-5 (10.7%). Conclusion HDV is highly endemic in Mauritanian blood donors indicating that a high number of them will develop chronic hepatitis, cirrhosis or hepatocellular carcinoma. Associated risk factors support nosocomial transmission of HDV. These data underline the need to reinforce HBV vaccination in newborns and in blood donors without HBV markers, together with screening for HDV in HBV-infected individuals.</p