[Analysis of hearing impairment causes in molecular diagnosis of deafness]

Deafness is one of the most frequent congenital hearing impairments. Knowledge of its causes will result in elimination of risk factors and applying prophylactic activities. It is recognized that about 40% of hearing impairments have genetic origin and 80% of these are autosomal recessive. Introducing molecular diagnosis to medical practice makes precise identification of hearing impairment and genetic counseling possible. The authors present results of DNA examination in patients with hereditary deafness, performed at the National Research Institute of Mother and Child in Warsaw. Genetic cause of deafness was confirmed in 60% cases.