Redheads are well-advised to stay out of the sun... but even if they do, their genetics makes them more prone to skin cancer mutations. For the first time, scientists have found a conclusive link between the "red hair" gene variant and a high mutational burden - which in this case, means a high number of mutagenic processes associated with skin cancer tumors.
In short, individuals with that gene variant are more likely to get melanoma mutations, according to the study by UK researchers published in Nature Communications. One of the lead authors, David Adams of the Wellcome Trust Sanger Institute, said in Science Daily, "It has been known for a while that a person with red hair has an increased likelihood of developing skin cancer, but this is the first time that the gene has been proven to be associated with skin cancers with more mutations."
Redheads are not the only ones who are at risk, it must be emphasized. The gene variant may be present but remain unexpressed, which means that there are people with dark hair who carry the same mutational burden as "gingers."
Red hair and freckles are indicators that an individual carries two R alleles (i.e., variants) of the melanocortin 1 receptor (MC1R) gene. Persons with freckles but no red hair have an 85% chance of carrying the R allele, while those with neither have an 18% chance of having the variant, according to BIOL312 @ UNBC.
Redhead or not, a person with an R allele will experience a higher than normal rate of spontaneous mutation caused by exposure to ultraviolet light - which is found in sunlight. Even without exposure to UV light sources, the person is still subject to a higher mutagenic rate, equivalent to the genetic burden of gaining an additional 21 years of age.