[OTOF-related auditory neuropathy spectrum disorder].

Unlabelled: Otoferlin () gene mutations are the most common cause of hereditary ANSD according to investigations in several countries.

The Aim: Of this study was to estimate the prevalence of mutations in Russian children with ANSD and evaluate audiological and clinical features of -related ANSD.

Patients And Methods: 28 children with bilateral ANSDwere enrolled in the investigation.

[Hearing loss due to mutations or lack of the gene coding protein stereocillin].

Objective: The description of a clinical picture and audiological features at the hearing loss caused by changes of a gene, coding protein stereocillin (MIM: 606440). Mutations in the numerous genes responsible for the inner ear proteins are the reason for congenital sensorineural hearing loss. The main cause of congenital bilateral sensorineural hearing loss in the Russian Federation are mutations in gene it reaches up 68% of cases identified in infancy.

[New recurrent extended deletion, including GJB2 and GJB6 genes, results in isolated sensorineural hearing impairment with autosomal recessive type of inheritance].

Hereditary hearing loss with the autosomal recessive type of inheritance of the DFNB 1 genetic type, caused by mutations in the GJB2 gene, is the main reason of innate non-syndromal hearing impairment in most developed countries of the world (including Russia). Intragenic point mutations prevail among the GJB2 gene defectors; however, extended deletions in the DFNB1 locus are also found with considerable frequency in some populations (for example, Spain, Great Britain, France, United States, and Brazil). Among the four known extended deletions, only one deletion affects directly the GJB2 gene sequence and was described in a single family.

[The mutation spectrum of the GJB2 gene in Belarussian patients with hearing loss. Results of pilot genetic screening of hearing impairment in newborns].

A total of 111 unrelated probands and their 8 sibs from Grodno oblast (Belarus) with bilateral isolated sensorineural hearing impairment were studied for the presence of mutations in the connexin 26--GJB2gene. Mutations were detected in 51 probands (46% of the sample). A significantly higher frequency of the GJB2gene mutations was observed in familial cases of the disease with the autosomal recessive type of inheritance (in 78% of families).