Gene-environment interaction in melanoma.

Gene-environment interaction can be defined as a different effect of an environmental exposure in people with different genotypes, or a different effect of a genotype in people with different histories of environmental exposure. Interaction applies when one stratum (high risk) responds differently to an exposure (sun) than another stratum (low risk). Genetic predisposition would appear to be a very important modifier of risk. This paper discusses the concept of gene-environment interaction applied to cutaneous melanoma through discussion of highly penetrant genes and their interaction with sun exposure, through discussion of low penetrant genes and their interaction with sun exposure, and by suggesting a new model for investigation of gene-environment interaction in melanoma. It is stressed that this area of investigation is extremely early in its development.