[Clinical and molecular genetic investigation of Waardenburg syndrome type 1].

Hypoacusis is a common sensory defect in humans which creates problems in communication. Heredity is essential in etiology of hypoacusis and deafness. Genes PAX3 and MITF were studied in patients with Vaardenburg syndrome in 14 unrelated families. Five mutation defects in the gene PAX3 were found. This provided the final diagnosis of the syndrome in these families.