Abstract
Alleles at the agouti locus determine the pattern formation of mouse hair pigments. Production of black hair pigment in the hair follicles of genotypically yellow mice was induced by irradiation with UV light at 254nm. The induced black pigment seems to be eumelanin that is normally found in the hair-bulb melanocytes of genotypically black mice judging by the electron-microscopic observation. The shift of production of melanin seems to occur within a single melanocyte.
