Density of dopa-positive melanocytes in dyschromatosis symmetrica hereditaria

Dyschromatosis symmetrica hereditaria, one of the hereditary diseases characterized by the presence of pigmented and hypopigmented spots on the extremities, was studied by the splitting dopa stain on the hypopigmented area. There were 190 +/- 58/mm2 dopa-positive cells, i.e. less than the normal value of the Japanese population. This suggests that the pigment anomaly in this disease may be due to the small number of melanocytes.