An estimate of the melanocyte mass in humans.

The size of the melanocyte system in humans was estimated as though all active melanocytes in the body were assembled in a single compact organ. Our estimates indicate that the epidermal melanocytes constitute the dominant part of the "melanocyte organ." In an adult human not recently exposed to sunlight, the functionally active epidermal melanocytes form a tissue 1.0-1.5 cm3. Other melanocytes, such as those in the mucous membranes, the follicles, and the eyes, constitute only a small proportion of the total melanocyte cell mass.