A frameshift mutation in DFNA5, which would lead to decreased expression, has been reported not to cause hearing loss [33]; therefore, the cause of hearing loss in subjects IV:2 and IV:3 is more likely to POU4F3 with the p.A336Vfs mutation derived from subject III:1, rather than DFNA5 with p.R261X mutation derived from subject III:2. Here, POU4F3 is linked to hearing loss disorder.