New faulty genes found that raise melanoma risk

The breakthrough by a team from Leeds University is particularly significant as the DNA faults linked to melanoma are the first to be revealed which are not associated with pigmentation or moles.

Known risks for melanoma include having fair skin, blue or green eyes, blond or red hair or a high number of moles. People who burn easily and those who have a family history are vulnerable, with eight associated genes having been already identified.

Around one in 25 people in the UK – about 2.3 million people – carry two copies of all three new gene faults identified and the researchers found that while the average risk of developing melanoma is about one in 60, this rises to one in 46 if someone has both copies of all three –- an increase of 30 per cent.

The discovery announced last night further raises the possibility doctors could in future identify people who are at greater risk of developing the illness, the UK’s sixth most common form of cancer.

In the study, experts scanned genes in blood samples from almost 3,000 Europeans with melanoma and compared them with those from the general public.

Lead author Prof Tim Bishop, based in the Cancer Research UK centre in Leeds, said: “We know that over-exposure to ultra violet increases the risk of developing melanoma, but this evidence shows that there are new additional genetic faults which can push up the risk further.

“It’s fascinating to discover these new melanoma risk factors and we expect that the results of similar studies underway will reveal even more.”

One DNA fault was found in the region of a gene called MX2 linked to narcolepsy – a disease, thought to be triggered by the immune system, which causes people to fall asleep spontaneously.

Another was found in a gene called ATM which is involved in DNA repair – preventing cancer-causing mistakes being passed onto daughter cells.

The third fault was found in the CASP8 gene, which plays a role in controlling cell growth by triggering automatic cell death.

Lesley Walker, Cancer Research UK’s director of cancer information, said: “These intriguing results provide deeper understanding of the causes of melanoma and provide a potential new approach to identify people most at risk of developing melanoma and other cancers.”

There are around 11,770 new cases of malignant melanoma diagnosed each year in the UK and these are mainly caused by overexposure to UV light.

Almost one third of all cases of malignant melanoma occur in people under 55 and it is the second most common cancer amongst young people aged 15-34. The highest incidence, however, is in people aged over 80 and more women than men are affected in the UK.

Over the past 25 years, rates of malignant melanoma in Britain have risen faster than any of the most common cancers.

Dr Walker added: “Cancer Research UK has invested heavily in research to identify tiny DNA changes to paint an overall picture of which regions of DNA could be linked to cancer – and we hope that research like this will reveal further genetic secrets to help us diagnose and treat the disease.

“The best way to reduce the risk of skin cancer, is to protect yourself from strong sun by covering up with clothing, spending some time in the shade, and applying at least SPF 15 sunscreen with four or more stars generously and regularly.”

The research by the Leeds team, together with experts from the GenoMEL consortium involving specialists from around the world working on the genetics of melanoma, was published in the journal Nature Genetics.