Familial melanoma: a complex disorder leading to controversy on DNA testing.

The initial enthusiasm generated by the discovery of the first susceptibility gene found for melanoma has slightly dampened over recent years. For the majority of melanoma families the underlying gene defect is still not known, so the search for other melanoma genes is continuing. Also, the increased risk of melanoma does not seem to be restricted to mutation carriers, but is present even in non-mutation carriers in melanoma families. The underlying defect of familial melanoma is less straightforward than previously thought; both environmental and hereditary risk modifiers intermingle in a perplexing way. This makes familial melanoma a complex disorder which deserves the close attention of both clinicians and researchers, especially as the opinion on gene testing in familial melanoma has not yet achieved consensus. On the one hand, there is a rising demand from families for genetic testing; on the other hand, there is the clinicians' concern about the value of such testing.