Genetic Counseling

Since the first international consensus paper in 2009, genetic counseling and testing options for melanoma have progressed rapidly. The number of known high-penetrance genes has expanded from P16/CDKN2A, P14arf/CDKN2A, and CDK4, to include BAP1, and several telomere-related genes, including TERT, POT1, ACD, and TERF21P. In addition, moderate-and low-penetrance genes have been added to MC1R as contributors to overall risk for melanoma, including: MITF, HERC2/OCA2, TYR, TYRP1, SLC45A2, and ASIP. Besides these genes that increase the inherited risk for melanoma, there are other genes that have well-established roles as high-penetrance genes for other cancer syndromes that appear to also serve as less-penetrant melanoma predisposition genes as well. These other cancer predisposition genes include BRCA1, BRCA2, PTEN, and CHEK2. (The xeroderma pigmentosum spectrum genes are not included in this chapter because genetic counseling for this subset of disorders requires additional considerations specific to the syndrome.) This chapter reviews the data supporting high-, moderate-and low-penetrance genes as relevant melanoma susceptibility genes, suggests a standardized protocol for risk assessment, and presents referral criteria for genetic assessment. The chapter also reviews rapidly progressing genetic testing technologies with an emphasis on selecting the most appropriate test and tailoring the testing process to each individual. Finally, a discussion of nuances related to genetic test interpretation, insurance discrimination, and the unique impact that genetic testing can have on individuals and society is explored.