The article reviews the latest achievements of molecular-genetic technologies in diagnosis of hereditary hypoacusis, statistics on hereditary hypoacusis morbidity in different countries. Arguments for genetic testing, diagnostic algorithm of congenital hypoacusis and trends in prophylaxis are considered. Presently 65 genes are identified which are related with syndromes and non-syndrome forms of neurosensory hypoacusis. In foreign countries about 200 mutations in 8 genes are diagnosed now. Pathological changes of the majority of genes lead to peripheral neurosensory hypoacusis as all these genes code proteins of the internal ear. In view of this, genetic testing makes topic diagnosis of the disease of the organ of hearing. Most of genetically confirmed hearing problems are indication for cochlear implantation. Prophylactic activity should be focused on explanation of the role and possibilities of genetic counseling and DNA diagnostic tests, promotion of knowledge of etiological structure of congenital hearing disorders. Active measures are necessary for early detection of genetic alterations among risk groups, early diagnosis of mutation carriers among couples of reproductive age with normal hearing.