The tyrosinases of normal and diseased human skin (naevi, malignant melanoma, vitiligo).

Extracts of healthy and diseased skin in vitiligo, naevi and malignant melanoma were electrophoresed on polyacrylamide gel. Melanin bands were visualized on the gel by Dopa reaction. The tyrosinases found in malignant melanoma were also present in naevocellular naevi. Additional dopa melanin bands were observed. Some bands which were not related to the presence of melanocytes varied with the level of the melanogenetic activity in the individual patients.