The current status of the pigment spread problem

Abstract

It is generally recognized that pigment spread is one of the most provocative and potentially important phenomena in the field of mammalian skin pigmentation. This phenomenon may be observed in a variety of mammalian species (1) including guinea pigs, cattle, sheep, pigs, mice, Dalmatian dogs and rarely in cases of recessive spotting in man. It consists essentially of a slow, progressive encroachment of superficial epidermal pigmentation from pigmented skin into adjacent white skin regions, and even from eu-melanic into pheomelanic skin regions when the two are contiguous. In the latter situation the rate of encroachment is much slower than when white skin is involved. This color transformation is entirely restricted to the superficial epidermis, so that hair color always remains unaffected.