Identification of two heterozygous deafness mutations in SLC26A4 (PDS) in a Chinese family with two siblings.

[pendred syndrome]

To detect genetic cause of two Chinese siblings (patient 1 and 2 ) with Pendred syndrome .Patients and their parents underwent clinical and genetic evaluations . To identify genetic mutations , sequencing of SLC 26 A 4 was carried out .Two siblings and their parents .Clinical evaluations showed that patient 1 suffered from bilateral postlingual progressive sensorineural hearing loss with enlarged vestibular aqueduct and slight diffuse multinodular goiter with euthyroid , and patient 2 suffered from bilateral prelingual progressive sensorineural hearing loss with enlarged vestibular aqueduct and no goiter with euthyroid . Furthermore , the sequence analysis of SLC 26 A 4 indicated that either of the two siblings presented a compound heterozygote for the c .919 A >G mutation in the splice site of intron 7 and for the c .1548 insC mutation in exon 14 . Their mother was a heterozygous carrier of the splice site mutation in intron 7 , and their father was a heterozygous carrier of the insertion mutation in exon 14 .M utation analysis identified a compound heterozygous mutation (c .919 A >G /c .1548 insC ) in SLC 26 A 4 in two Chinese siblings with Pendred syndrome . Also , c .1548 insC was first reported in the Chinese population . Although the two siblings from the same family carried the same genotype , they presented different phenotypes .