Detection of KCNN4 and KPTN gene mutations in Chinese DFNA4 family / 中国耳鼻咽喉头颈外科

ABSTRACT

OBJECTIVE To investigate whether the KCNN4 gene and KPTN gene contribute to a Chinese non-syndromic hearing loss pedigree linked to DFNA4 with positional candidate approach. METHODS The complete coding region of the two genes were amplified with polymerase chain reaction (PCR), and bidirectional sequencing of the PCR products was subsequently applied in the 36 family members to identify the possible mutations or polymorphisms in the candidate genes. RESULTS Sequence analysis of coding regions and splice sites of the two candidate genes in 36 members including 12 hearing-impaired individuals in family Z002 failed to demonstrate any deafness-causing mutations of KCNN4 gene. There was one heterozygous mutation identified in exon10 coding sequence (942C/T) of KPTN gene, which did not result in amino acid change (P302P) as a repoerted synonymous SNP site (rs2293424). This SNP site did not cosegregate with the phenotype of family Z002. CONCLUSION Our study excluded the two candidates, KCNN4 and KPTN , as the causative genes involved in this Chinese DFNA4 pedigree.