Red hair gene variation drives up skin cancer mutations

“Identifying this subset of patients could [someday] help decrease the risk of melanoma and ultimately save lives”, said Dr. Michele Green, a dermatologist at Lenox Hill Hospital in New York City. It is thought that the type of skin pigment associated with R alleles allows more UV to reach the DNA and thus facilitates the creation of tumours in people with red hair.

The red hair gene version of MC1R does not offer much tanning or sun protection.

The research showed that even a even a single copy of a red hair-associated MC1R gene variant increased the number of mutations in melanoma skin cancer; the most serious form of skin cancer.

David Adams, MD, joint lead researcher, Wellcome Trust Sanger Institute, said in a news release, “Unexpectedly, we also showed that people with only a single copy of the gene variant still have a much higher number of tumor mutations than the rest of the population”.

Author Professor Tim Bishop, from the University of Leeds, said: “This is the first study to look at how the inherited MC1R gene affects the number of spontaneous mutations in skin cancers and has significant implications for understanding how skin cancers form”. Researchers analysed DNA from more than 400 people and found 42 per cent more sun-associated mutations in tumours in people carrying the gene variant.

In a study published Tuesday in the journal Nature Communications, an global team led by cancer geneticists from the United Kingdom’s Sanger Institute scoured the “germline” genes of 273 melanoma patients (more or less, the DNA carried by all of their cells over a lifetime) for evidence of their MC1R carrier status.

What this study now shows is that MC1R gene variants could also increase the risk of melanoma mutations, once these tumours have formed.

Surprisingly they also discovered the gene increased levels of other skin tumour mutations which aren’t related to exposure to UV rays, which suggests it’s involved in cancer processes not caused by sunlight.

‘It has only been possible due to the large-scale data available.

This suggests that biological processes exist in cancer development in people with MC1R variation that are not exclusively related to ultraviolet light. But they make up 16% of the world’s population of melanoma patients.

The study supports the idea that everyone needs to be careful about sun exposure.

Writing in the journal Nature Communications, an global team of researchers describe how they analysed existing genetic data and samples from 405 melanoma patients.

While people with two copies of the gene will have ginger hair, freckles and pale skin and probably know to take extra care in the sun, those with one copy may not realise they are at risk.

“People with red hair have a different type of melanin than people who don’t have red hair – and the type of melanin that redheads have is less able to protect them from the sun”, said Adams.

While more research is underway, experts caution red-heads to protect themselves from strong sun exposure.

The summer sun may encourage us to spend more time outdoors, but it isn’t always kind to our skin once we’re there.

“Sunscreen helps protect the parts you can’t cover – use one with at least SPF15 and four or more stars, put on plenty and reapply regularly”.