GJB2 and GJB6 gene mutations found in Indian probands with congenital hearing impairment.
Genetically caused deafness is a common trait affecting one in 1000 children and is predominantly inherited in an autosomalrecessive fashion. Several mutations in the GJB2 gene and a deletion of 342 kb in GJB6 gene (delGJB6-D13S1830) have been identified worldwide in patients with hearing impairment. In the present study, 303 nonsyndromic hearing-impaired patients (140 familial; 163 sporadic) were examined clinically and screened for mutations in GJB2 and GJB6 genes. Mutations in GJB2 gene were found in 33 (10.9%) patients of whom six (18.2%) were carriers for the mutant allele. The most frequent mutation was p.W24X accounting for 87% of the mutant alleles. In addition, six other sequence variations were identified in the GJB2 gene viz., c.IVS1+1G>A, c.167delT, c.235delC, p.W77X, p.R127H (polymorphism), p.M163V. None of the samples showed del(GJB6-D13S1830) or any point mutations in GJB6 gene.
Padma
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G
Department of Genetics, Osmania University, Tarnaka, Hyderabad 500 007, India. padmatirunilai@gmail.com
Ramchander
P V
PV
Nandur
U V
UV
Padma
T
T
D000328:Adult; D016022:Case-Control Studies; D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000235:genetics*; D003241:Consanguinity; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D034381:Hearing Loss / Q000151:congenital* / Q000453:epidemiology / Q000235:genetics*; D006801:Humans; D007194:India / Q000453:epidemiology; D008297:Male; D009154:Mutation / Q000235:genetics*; D015995:Prevalence; D055815:Young Adult
D000075302:Connexin 30; D017630:Connexins; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; D000072259:Connexin 26