A Novel mutation in the SLC26A4 gene in a Chinese family with Pendred syndrome.

[pendred syndrome]

To investigate the mutations in the SLC 26 A 4 gene in a Chinese patient with Pendred syndrome .The diagnosis of Pendred syndrome was confirmed by the family history , pure tone audiogram , perchlorate discharge test (PDT ), and computed tomography (CT ) of the temporal bone . DNA extraction , PCR and DNA sequencing were performed according to standard procedures . Mutations in the SLC 26 A 4 gene were compared with 100 unrelated subjects to exclude common polymorphism . Splice-site mutation was further confirmed by restriction enzyme length polymorphism (RFLP ) with the specifically designed primers .The proband presented with typical features of bilateral sensorineural deafness since childhood and goiter development in the early adulthood . Thyroid studies disclosed euthyroidism with elevated thyroglobulin , but negative for PDT . Marked enlargement of bilateral vestibular aqueduct (>1 .5 mm ) was found by CT of the temporal bone . A novel SLC 26 A 4 splice-site mutation c .1263 +1 G >A (IVS 10 +1 G >A ) was identified in compound heterozygosity with the missense mutation c .1079 C >T (p .A 360 V ) in the proband . Both mutations were not found in the 100 unrelated Chinese .O ur results support previous findings that Pendred syndrome can be caused by compound heterozygous mutation in the SLC 26 A 4 gene , in which IVS 10 +1 G >A is a novel pathogenic mutation .