Rare, highly penetrant variants in a small number of genes (CDKN2A and CDK4) are associated with familial melanoma. These variants show an autosomal dominant inheritance pattern. Only 1–2% of melanomas are due to pathogenic variants.1,2
Having a first-degree relative with melanoma approximately doubles an individual’s risk of developing melanoma. Having relatives who are affected with multiple melanomas or at a younger age further increases the risk of developing melanoma.3
Features within a family that are suggestive of increased risk of carrying a pathogenic variant for familial melanoma include having three or more relatives affected by melanoma on the same side of the family.
Other features and red flags within a family are:1
- multiple melanomas in the same person
- melanoma diagnosed <40 years of age
- ocular melanoma
- pancreatic cancer