Genetic epidemiology of melanoma.

Melanoma incidence has risen in many Caucasians populations over the last 20 years and research on the potential environmental and genetic risk factors has led to some interesting new findings but also to many more questions. The relationship between melanoma and ultraviolet radiation is complex and this area of research is controversial especially regarding the use of sunbeds and sunscreens. In terms of genetic factors, the discovery of two genes CDKN2A and CDK4 has been a great advance with more understanding of melanocyte biology in relation to defects in senescence. For phenotypic risk factors such as fair skin and high numbers of naevi, the role of genetic factors is clearly evident but these traits are complex and the discovery of genes involved in skin pigmentation and naevi formation is not an easy task. Research on the MC1R gene has not only shown the importance of this gene in hair and skin pigmentation but also in senescence and immunity. Functional studies involving CDKN2A and MC1R are leading to important new findings. There is also some hope regarding the use of micro-arrays in helping to dissect many genetic events in melanoma. The collection of large datasets including family, twin and case-control studies as well as tumour banks with collaborations between countries will hopefully lead to more discoveries. For the primary and secondary prevention of this tumour, efforts need to be sustained in public health campaigns on sun exposure and the recognition of individuals at high risk.