WFS1 and Hearing impairment: While in the four dominant families, we identified four dominant deafness-related heterozygous variants, c.61_62insGGACCCGCAGTTGCAGC in TIMM8A (OMIM 300356) for Family F, c.733delA in MITF (OMIM 156845) for Family G, p.H313Y in WFS1 (OMIM 606201) for Family H, and p.A677T in WFS1 (OMIM 606201) for Family I, co-segregating with the hearing impairment (Figure 1).