The role of UV and pigmentation are very difficult to control for in human studies, and mechanisms difficult to infer based on statistical association with melanoma. The animal models are not representative of the human situation. But on the other hand, animal studies can be useful for basic studies that will ultimately help in building up a picture of the overall network of in vivo cellular behavior and intra and inter cellular pathways contributing to melanoma progression and the effects (or not) of UV radiation in individuals with MC1R variants. This review describes that, although the Mc1r is a determinant of coat color phenotype as the MC1R is a determinant of hair and skin color in humans, deficiency of the Mc1r in mice is associated with a paradoxical lower incidence of melanoma.