Two Chinese families with Pendred's syndrome - Radiological imaging of theear and molecular analysis of the pendrin gene

We report two families in whom the index cases satisfied the classical diag nostic criteria of Pendred's syndrome. In family I, two siblings were deaf, and one was normal. In family II, both parents and two offspring were deaf . Computed tomography scans performed in five of six of these deaf individu als showed enlarged vestibular aqueducts in all cases, and Mondini cochlea only in family II. Affected members in family I were compound heterozygotes inheriting the paternal allele with a novel mutation S398del in exon 10 an d a maternal allele with two mutations IVS13+9C -->G in intron 13, in addit ion to H723R. In family II, the mother and one child carried both the novel intronic IVS8-2A -->G and H723R mutations, whereas the father and index ca se were homozygous for the IVS8-2A -->G mutation. A perchlorate discharge t est was positive in 50% of cases tested. In conclusion, we concur that radi ological and molecular studies should be performed for confirmation of Pend red's syndrome. We report, for the first time, a Pendred's syndrome family in which affected members had three mutations, as well as a second family i n whom the intermarriage of two Pendred's syndrome patients resulted in Pen dred's syndrome offspring.