Department of Otolaryngology and Sensory Organ Surgery, Osaka University Graduate School of Medicine, Suita, Osaka, Japan.
Although the bases for both the sporadic and inherited forms of Ménière's disease (MD) remain undefined, it is likely to be multifactorial, one of the factors being a genetic predisposition. Recently, genetic association studies on complex diseases have become very popular and most of them are case-control studies using single nucleotide polymorphisms (SNPs) as markers. Mutations/polymorphisms in KCNE potassium channel genes might play a causative role in MD, because KCNE potassium channels have been suggested to be present and active in transmembrane ion and water transports in the inner ear. In the present study, to identify MD susceptibility genes, we have conducted a genetic association study with optimized sampling, optimized phenotyping/genotyping, and a selection of KCNE genes as the candidate genes. The SNPs analyses identified 112G/A SNP in the KCNE1 gene and 198T/C SNP in the KCNE3 gene in 63 definite MD cases as well as 205 and 237 non-MD control subjects. For both KCNE1 and KCNE3 genes, a significant difference in frequency of each SNP was confirmed between MD cases and non-MD control subjects. The result indicates that 112G/A SNP in the KCNE1 gene and 198T/C SNP in the KCNE3 gene could determine an increased susceptibility to develop MD.