ABCB6 and familial progressive hyper- and hypopigmentation: Three known subtypes of this disease are dyschromatosis symmetrica hereditaria (DSH), dyschromatosis universalis hereditaria (DUH), and familial progressive hyper- and hypopigmentation (FPHH); they result from autosomal dominant inheritance without systemic involvement; DSH, DUH, and FPHH are caused by adenosine deaminase acting on RNA1 gene (ADAR1) (Miyamura et al., 2003), ATP binding cassette subfamily B member 6 gene (ABCB6) (Zhang et al., 2013), and KIT ligand gene (KITLG) (Amyere et al., 2011), respectively.