Absence of GJB3 and GJB6 mutations in Moroccan familial and sporadic patients with autosomal recessive non-syndromic deafness

Prevalence of the mitochondrial A 1555G mutation in Moroccan patients with non-syndromic hearing loss

“…This phenotype variability observed in the members of our Moroccan pedigree suggested the involvement of nuclear modifier genes(s) in the development of deafness phenotype since two out of three families did not have a previous history of exposure to aminoglycosides and no subjects had a mutation in GJB2, GJB3 and GJB6 genes [20]. It was demonstrated that phenotypic variability could be due to additional mutations in a nuclear gene [31], to other variants in the mitochondrial DNA, or to interactions of genetic and environmental factors [14,21].…”

“…In addition, one hundred Moroccan normal hearing individuals were tested as controls. All patients were previously tested negatives in GJB2, GJB3 and GJB6 genes [20]. Participating members of families and sporadic cases underwent general otological examinations and pure-tone audiometry with air and bone conduction at 250, 500, 1000, 2000, 4000, and 8000 Hz.…”

“…Several studies were performed in Moroccan patients with sensorineural hearing loss to describe genetic abnormalities in nuclear genes such as GJB2, GJB3, GJB6, ESPN and MYO7A [18][19][20], but to date no study was undertaken to evaluate mitochondrial DNA mutations impact in the 12S rRNA gene in hearing loss. Here, we report the first mutational screening of the A1555G mitochondrial mutations in Moroccan patients with sensorineural hearing loss to assess the prevalence of this mutation.…”

GJB3/GJB6 screening in GJB2 carriers with idiopathic hearing loss: Is it necessary?

“…Great efforts have been made toward clarifying the contributions of GJB3 and GJB6 mutations to deafness in diverse populations during the past decades . To address this issue, Yang et al screened 380 Chinese (260 with NSHI and 120 with normal hearing) for variants in eight connexin genes.…”

Genetic and molecular analysis of the CLDN14 gene in Moroccan family with non-syndromic hearing loss

“…Identifying genes underlying hearing loss represents a powerful tool for discovering the molecular mechanisms that control the development, function and maintenance of the auditory system. In Moroccan population, we described the contribution of the GJB2 ,[111213] GJB6 ,[14] GJB3 ,[14] 12sRNA ,[15] ESPS ,[16] TPRN [17] and TMPRSS3 [18] genes in inherited deafness. In order to add to the knowledge of genes involved in deafness in our population, we performed a genetic analysis of the CLDN14 gene in Moroccan family with non-syndromic hearing loss (NSHL) with unknown etiology.…”