They counted the number of moles and measured the amount of freckles they had on a scale of 0 to 100. Once the identical twins reached the age of 50, there was an increased similarity in the number of pairs of individual moles. The researchers suggest that once people reach a certain age some genes become more active, and this may trigger a susceptibility to skin cancer. Sun exposure still has a part to play as it may also affect the way genes work in producing moles. Professor Rona Mackie, an expert in skin cancer from the University of Glasgow, said it was important that people with a family history of melanoma did not panic.
Malignant melanoma is the least common, but most aggressive form of skin cancer.
Early treatment is vital as it accounts for the vast majority of deaths from skin cancer. The BBC is not responsible for the content of external internet sites Links to other Health stories are at the foot of the page.