Predictive testing of the melanocortin 1 receptor for skin cancer and photoaging.

Genetic predisposition to melanoma and nonmelanoma skin cancer extends far beyond the Fitzpatrick phenotype classification scheme. Specific alleles of the gene that codes for the malnocortin 1 receptor are predictive of skin cancer risk independent of skin type and hair color. The ability to identify high risk patients independent of the red hair phenotype may help to modify routine sun and skin monitoring behaviors. In addition, as this increased skin cancer risk is likely due to impaired UVA and UVB defence mechanisms, consideration of genetic predisposition may also be appropriate for patients undergoing psoralen + UVA (PUVA) or UVB treatments for various cutaneous disorders, such as psoriasis, eczema, and vitiligo. Testing aimed at improving prognostication may serve to limit the influence of certain risk factors.