title: Etiology and associated GJB2 mutations in Mauritanian children with non-syndromic hearing loss.
abstract: Origins of all hearing impairment forms may be divided into genetic mutations and acquired influence. Both carry damage to the inner ear structure resulting in a mild to profound dysfunction of the auditory system. The purpose of this study was to assess the different etiologies of deafness in two reference centers for hearing-impaired children in Nouakchott/Mauritania. Data on gender, age, consanguinity, etiology and family history of deafness were gathered by interviewing the custodians of 139 children with hearing loss. DNA of pupils with hereditary non-syndromic deafness was then screened for GJB2 mutations by sequencing methods. Postnatal hearing loss was found in 36 (25.8 %) out of the 139 children surveyed. The main etiologies of this group were infections caused by meningitis (12.9 %) and measles (2.8 %). Unknown and ototoxic origins accounted for, respectively, 5.7 and 3.5 %. In 103 (74.1 %) children, deafness was identified near after the time of birth and, therefore, presumed as congenital. 56.8 % of deaf children had consanguineous parents. Two GJB2 mutations, c.del35G with an allele frequency of 4.7 % and R32C (3.7 %) were detected. Infections such as meningitis and measles were the most prevalent causes of postnatal deafness. In cases of congenital hearing impairment, two GJB2 allele variants, i.e., del35G and R32C (3.7 %) were detected. Extended genetic testing is recommended for a more comprehensive determination of congenital causes.
authors.affiliation: Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritania.|Unité de Recherche physiologie et physiopathologie, Université Abdelmalek Essaadi, Tétouan, Morocco.
authors.forename: Ely Cheikh Mohamed
authors.initials: EC
authors.lastname: Moctar
authors.affiliation: Laboratoire de Génomique Biomédicale et Oncogénétique, IPT, Tunis, Tunisia.
authors.forename: Zied
authors.initials: Z
authors.lastname: Riahi
authors.affiliation: Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritania.
authors.forename: Hala
authors.initials: H
authors.lastname: El Hachmi
authors.affiliation: Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritania.
authors.forename: Fatimetou
authors.initials: F
authors.lastname: Veten
authors.affiliation: Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritania.
authors.forename: Ghlana
authors.initials: G
authors.lastname: Meiloud
authors.affiliation: Institut de la Vision, INSERM UMRS 1120, UPMC-Paris 6, Paris, France.
authors.forename: Christine
authors.initials: C
authors.lastname: Bonnet
authors.affiliation: Laboratoire de Génomique Biomédicale et Oncogénétique, IPT, Tunis, Tunisia.
authors.forename: Sonia
authors.initials: S
authors.lastname: Abdelhak
authors.affiliation: Unité de Recherche physiologie et physiopathologie, Université Abdelmalek Essaadi, Tétouan, Morocco.
authors.forename: Mohammed
authors.initials: M
authors.lastname: Errami
authors.affiliation: Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritania. houmeida@hotmail.com.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Houmeida
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D000072259:Connexin 26; D017630:Connexins / Q000235:genetics*; D003638:Deafness / Q000175:diagnosis / Q000209:etiology* / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D005819:Genetic Markers; D005820:Genetic Testing; D006801:Humans; D008297:Male; D008435:Mauritania; D009154:Mutation; D012307:Risk Factors; D055815:Young Adult
chemical_list: D017630:Connexins; C000607042:GJB2 protein, human; D005819:Genetic Markers; D000072259:Connexin 26
keywords: Children; Etiology; GJB2; Hearing loss; Mauritania