People with inherited cancer genes may have more control over their risk of developing the disease than previously thought.
A study by an international team of scientists, led by Cancer Research UK, challenges the notion that inherited cancer genes are so powerful that they are not affected by external factors such as the environment.
Research published in the Journal of the National Cancer Institute1, suggests people with a common inherited cancer gene (CDKN2A) may be able to reduce their risk of developing malignant melanoma – the deadliest form of skin cancer – by protecting themselves in the sun.
The findings underscore the importance of research into hereditary cancer genes and the way that lifestyle and environmental factors can moderate risk.
The team, led by Professor Tim Bishop from Cancer Research UK’s Genetic Epidemiology Lab in Leeds, analysed 80 families from Europe, Australia and the United States, all of whom had documented mutations of the gene CDKN2A and at least two cases of malignant melanoma. Mutations in the CDKN2A gene are the most common cause of inherited susceptibility to melanoma.
They found that all carriers of CDKN2A had a higher than average risk of developing melanoma compared with the general population. However, gene carriers who lived in Australia had an estimated 32 per cent risk of developing melanoma by the age of 50, compared to just 13 per cent for those living in Europe (UK, France, Italy, Sweden and the Netherlands.) By the age of 80 that risk increased to an estimated 91 per cent in Australia, compared with 58 per cent in Europe.
Prof. Bishop says: “It may seem obvious to say that people living in a hot climate are more likely to develop melanoma. What is so interesting about these findings, however, is we have shown for the first time that people who are automatically at a higher risk of developing the disease may be able to moderate their risk according to environmental factors.
“The study will help us reach a greater understanding of how various factors combine, not only in skin cancer but with other forms of the disease too.”
Professor Gordon McVie, Director General of Cancer Research UK, says: “If someone is told they have an inherited cancer gene, understandably they can often feel helpless. What this study shows is that people still have some control over their destiny and it may have important benefits for further work into the study of cancer genetics.
“The study also reinforces the importance of everyone covering up in the sun. The number of people diagnosed with skin cancer is growing each year in the UK. Yet, by following Cancer Research UK’s simple SunSmart guidelines, we can all reduce our risk.”
- JNCI94 pp.894-903
SunSmart lays out the following guidelines for everyone to follow:
- avoid the sun at its height (usually 11am-3pm)
- take care never to burn
- use shade wherever possible: trees, umbrellas, shade
- take extra special care of babies’ and children’s delicate skin
- wear a wide brimmed hat and sunglasses with UV protection
- cover up with tightly woven, loose fitting clothes: long sleeves, trousers, skirts
- always use a broad spectrum sunscreen (SPF 15 or higher) with UVA protection, even if you have a tan
- avoid using sunbeds or tanning lamps
- check your skin regularly and report any unusual changes without any delay