Melanocortin-1-receptor gene and sun sensitivity in individuals without red hair

Susceptibility to sunburn, photoageing, and skin cancer is inversely relate d to an individual's ability to tan after sun exposure. We examined variant s in the melanocortin-1-receptor (MC1R) gene in individuals from Ireland an d the UK. We found evidence of an association between the degree of tanning after repeated sun exposure, and the number of variant alleles present. He terozygotes were intermediate between wild-type individuals and those with two variant alleles. We suggest that MC1R gene status therefore determines sun sensitivity in people without red hair.