Novel heterozygous mutation c.662_663insG compound with IVS7-2A>G mutation in SLC26A4 gene in a Chinese family with Pendred syndrome

Abstract

Objective: Pendred syndrome is one of the most common hereditary determined diseases in patients with syndromic sensorineural hearing impairment. Mutations in the SLC26A4 gene are a major cause of Pendred syndrome. However, Pendred syndrome is quite rare in China. This investigation aims to identify genetic cause of a Chinese family with Pendred syndrome.

Methods: Clinical and molecular evaluations were conducted in a Chinese family with Pendred syndrome.

Results: A novel SLC26A4 c.662_663insG mutation was detected in compound heterozygosity with IVS7-2A>G. No FOXI1, KCNJ10 or GJB2 pathogenic mutation was found. The novel mutation c.662_663insG (p.G221) locates in SLC26A4 gene exon 6, and cause frameshift mutation on pendrin protein transmembrane domain five.

Conclusion: The compound heterozygosity of the novel c.662_663insG and IVS7-2A>G mutations in the SLC26A4 gene was considered to be the cause of Pendred syndrome in the proband. This study also supplemented the mutation spectrum of Pendred syndrome.