[Diagnosis of genetically determined hearing impairment--difficulties and problems]

In terms of growing interest in molecular analysis of genetically determined hearing impairment, it is of clinical importance to know problems and obstacles that arise on the way to molecular diagnosis. Although for clinicians a genetic factor as a reason for hearing problem is easier accepted, still an understanding the limits of such identification remains unclear. Technical issues, as well as social and legal aspects of genetic analysis are described. Authors try to explain why such impressive progress in understanding of hearing loss physiology, especially from the genetic point of view, does not have its transfer into clinical practice.