A replication study on proposed candidate genes in Meniere's disease, and a review of the current status of genetic studies

Objective: Multiple candidate genes have been presented for Meniere's disease (MD), but to date no positive replications have been reported. We review here all the previously proposed candidate genes for MD and report our results on the analysis of six such genes, AQP2, KCNE1, KCNE3, HCFC1, COCH, and ADD1. Study sample: A well-defined sample set of 38 sporadic and 21 familial Finnish MD patients. Design: Mutation analysis, case-control study, and review of literature. Results: A polymorphism rs1805127 in the potassium channel gene, KCNE1, was associated with MD in sporadic (p = 0.011), but not familial patients (p = 0.62). In addition, we identified four novel unique variations in the KCNE1 gene. PolyPhen and Mutation Taster analyses indicated that at least one of the variations c.259T > C; p. Trp87Arg is probably damaging to the coded protein. Conclusions: Our review of the reported candidate genes shows that the current understanding of the genetic factors contributing to the development of MD is limited, and that the study of its etiology would benefit greatly from more comprehensive genetic knowledge.