Hearing impairment is one of the most common disorders of sensorineural function and is an economically and socially important cause of human morbidity. The incidence of profound prelingual deafness is about one per 1,000 at birth. Mutations in the GJB2 and GJB6 genes for DFNB1 (13q12) are responsible for about half of all cases of autosomal recessive prelingual hearing loss. The Volga-Ural region of Russia is of particular interest, because its ethnic populations mostly belong to the Turkic, Finno-Ugric, and Slavonic linguistic groups and have complex ethnogenesis and combine the Caucasian and Mongoloid components in various proportions. A total of 100 patients of Tatars, Russian or mixed ethnicity and 768 population samples were analyzed by PCR-SSCP and sequencing in the GJB2 gene. The GJB6 deletion and the common non-syndromic deafness-causing mitochondrial mutations were also tested when appropriate. The 35delG mutation was p redominant among patients from Volga-Ural region (frequency is 0.014). Also the 312del14 mutation in GJB2 is the second most frequent cause of non-syndromic hearing impairment in Volgo-Ural region. Our data testify to the founder effect and suggest an eastward distribution of 35delG, since its frequency in Finno-Ugric populations gradually decreases from Estonia to Komi. The question whether Volga-Ural region could be one of the founder sources for the 235delC and 167delT mutations, widespread in Asia and Israel community, is open. Also, the 312del14 mutation in GJB2 is the second most frequent cause of non-syndromic hearing impairment in Volga-Ural region.