When Homo sapiens left Africa and had to adapt to less sunny climates, there was a mutation in one of the genes responsible for regulating the synthesis of melanin, the MC1R gene, which involved a discoloration of the skin. This discoloration allowed for better absorption of vitamin D, necessary for growth, but it also increased the risk of developing skin cancer in adulthood. This mutation is most common among people from Mediterranean regions such as Spain, Portugal, Italy and Israel, presenting in about 10-20% of the population.