CDKN2A and melanoma: The COSMIC database of over 13 000 cancer samples (Forbes et al, 2006) (http://www.sanger.ac.uk/genetics/CGP/cosmic/) lists p16 point mutations in 15% of all tested samples, including nearly every cancer type tested, although the frequency varies with type and culture status (22% for melanoma, 9% for all uncultured melanoma samples).