Previous studies have concentrated on human hearing loss genes [2, 5], but we have compiled a larger list of nearly 700 genes based on human and mouse studies, and from this we have identified multiple candidate genes among our outliers, including FSCN2, SYNJ2, FBXO11, NAV2, TMC2, ERCC6 and PKHD1L1. Of the 185 known human deafness genes, 118 are also mouse deafness genes (Additional file 2: Table S3), suggesting that mouse deafness genes are indeed good candidate human deafness genes. The gene discussed is NAV2; the disease is deafness.