SASH1 and dyschromatosis universalis hereditaria: Of these, more than three-quarters have been reported from Japan, India, China and other Asian countries.3 The prevalence of DUH is estimated to be 0.3 per 100 000.2 The incidence is slightly higher in women than in men.4 However, 15 out of 22 SASH1 mutation-related cases occur in men (Table 1).1,3,5–14 The mechanisms underlying these sex-related differences remain unclear.