We have analyzed DNA from peripheral blood of 42 cases of familial melanoma for germline mutations in exon 15 of the BRAF gene. No evidence of mutation was found. We have also analyzed DNA extracted from secondary melanoma from two members of these families. These results were also negative. In addition we have searched for exon 15 BRAF mutations in 24 samples of secondary melanoma from 22 cases of sporadic melanoma and detected the 1796T>A BRAF mutation which leads to a substitution of valine by glutamic acid at position 599 (V599E) in six samples. Peripheral blood DNA from two of these tumor-positive cases of sporadic melanoma were negative for the V599E BRAF mutation. This mutation therefore appears to be a somatic mutation associated with melanoma development and/or progression in a proportion of affected individuals.
Copyright 2003 Wiley-Liss, Inc.