Allele diversity and GJB2-associated hearing loss frequency in Ossetian patients from North Ossetia

Pathogenic variants in the GJB2 gene are the most common molecular cause of nonsyndromic autosomal recessive sensorineural hearing loss type 1 (DFNB1). The aim of the work was to evaluate the spectrum of genetic variants and the proportion of GJB2-associated hearing loss in patients with hereditary non-syndromic hearing disorders in the Ossetian population from the Republic of North Ossetia-Alania. Sanger sequencing of 1 and 2 exons of the GJB2 gene, followed by analysis of the variation in the number of copies of loci by multiplex ligase-dependent amplification (MLPA) was carried out. The study was conducted on a sample of 83 patients with hereditary nonsyndromic sensorineural hearing loss from 74 unrelated families from the population of Ossetians of the Republic of North Ossetia-Alania (RSO-Alania). The cause of nonsyndromic sensorineural hearing loss in Ossetians in the RSO-Alania, due to pathogenic variants of the GJB2 gene, was confirmed in 26.8% of patients. Two genetic variants (GJB2(NM_004004.6):c.358_360del (p.Glu120del)) - 54.2% и GJB2(NM_004004.6):c.35del (p.Gly12ValfsTer2) - 37.5%) account for 91.7% of pathogenic alleles of the GJB2 gene in Ossetian patients.

hereditary diseases, nonsyndromic sensorineural hearing loss, GJB2 gene, mutations, ethnic and age characteristics, North Ossetia

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