Hereditary nonsyndromic autosomal recessive hearing loss in Yakutia: molecular-genetic and cochlear implantation aspects

Aim of study: To study the reasons of nonsyndromic sensorineural hearing loss, one of frequent hereditary pathologies in the Republic of Sakha (Yakutia), the search of mutations is conducted in the coding region of GJB2 gene in 79 patients from 65 families with a sensorineural hearing loss of III-IV degree (moderate and profound).
Results. In GJB2 gene in patients from the Republic of Sakha (Yakutia) we identified 5 different recessive mutations 35delG, V37I, 312-326del14, 333-334delAA, R127H and three sequences variant V27I, M34T, E114G. In Caucasian patients (Russians, Ukrainians, Ingush) the mutations 35delG (41.7%), 312-326del14 (4.2%), 333-334delAA (4.2%) were found. In Yakut patients with non-syndromic sensorineural hearing loss the mutations 35delG (2.1%), V37I (2.1%), R127H (1.0%) and sequences variants V27I (6.3%), M34T (1.0%), E114G (1.0%) were identified. GJB2 mutations were found in 50.1% Caucasians patients and 7.2% Yakut patients.
Conclusion. Low frequency of GJB2 mutations in Yakut individuals with non-syndromic sensorineural hearing loss, can testify to the presence in Yakut population of mutations in other genes, responsible for infringement of sound perception process.

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