P.K. RAMAZANOVA, Yu.A. DZHAMALUDINOV, M.Z. SAIDOV

Dagestan State Medical Academy, 1 Lenin Square, Makhachkala, Russian Federation, 367000

Ramazanov P.K. — postgraduate student of the Department of Otorhinolaryngology, tel. +7-960-418-08-86, e-mail: [email protected]

Dzhamaludinov Yu.A. — D. Med. Sc., Professor of the Department of Otorhinolaryngology, tel. +7-928-230-50-71, e-mail: [email protected]

Saidov M.Z. — D. Med. Sc., Professor, Head of the Department of Pathological Physiology, tel. +7-988-300-90-45, e-mail: [email protected]

The study included 52 patients with sensorineural hearing loss (SNHL). The frequency of pathological mutations in connexin 26 gene was studied, as well as the mode of inheritance of these mutations and the production of autoantibodies to myelin proteins. It is shown that the hereditary forms of sensorineural hearing loss in the Dagestani population, the most frequent mutations in the connexin 26 gene are 35delG and 167delT mutations. The autosomal recessive mode of inheritance dominates in up to 80% cases. The autosomal dominant mode of inheritance was observed on average in 20% cases. SNT progression is associated with the increased production of autoantibodies to myelin (PO) protein. In progressive non-hereditary SNT, there were positive results in 36.3% cases. The maximum number of positive cases (presence of autoantibodies) was observed in non-hereditary progressive SNT, which allows to suggest a pathogenetic significance of autoantibodies to myelin (PO) protein in the progression of hearing loss. According to the clinical and genealogical data, the latter were more common in autosomal recessive type of inheritance.

Key words: sensorineural hearing loss, mutations in connexin 26 gene — 35delG, 167delT and 235delS, autoantibodies to myelin proteins.

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