The CDKN2A gene is the most important susceptibility gene for skin melanoma. Carriers of a mutation in this gene not only have a high risk to develop one or more melanomas at a young age, but also have an increased risk for other cancers, especially pancreatic cancer and upper airway cancer (mouth and throat). We have developed a scoring system, “CDKN2A Mutation (CM)-Score”, to predict the probability of a CDKN2A mutation in a melanoma family. The scoring system is based on clinical information of melanoma diagnoses in the family, and additionally includes diagnoses of pancreatic and upper airway cancer. Clinical information of 1227 Dutch and 421 Swedish melanoma families was used to create and validate CM-Score. We show that CM-Score is an accurate and reliable prediction tool that is easy to use in clinical practice. (By Dr. Thomas P. Potjer, http://jmg.bmj.com/content/early/2018/04/16/jmedgenet-2017-105205)