This isn't shocking, given the genetic component in so many diseases, but it's another piece of news to make you wear your sunscreen and ask if someone in your family has had skin cancer. Melanoma, as well as other skin cancer types, have been proven heritable. Researchers at the University of Queensland in Australia found that if one twin in a set has melanoma, the other's risk increases 10 fold, while a fraternal twin's risk more than doubles if one has had it. They also found that having a sibling or parent with skin cancer also means that you're more likely to have some kind of skin cancer as well, though not only the type your relative had.
The takeaway? Some skin cancers, like some breast cancers, have a genetic factor. So if a loved one has had it, make sure you get frequent checks at the dermatologist, wear SPF daily, and learn the facts about self-examination.