Black men have genetic variants that put them at greater risk of developing prostate cancer than white or Asian men, a study published last night has revealed.
The genetic analysis, led by scientists at The Institute of Cancer Research, London, UK, and the University of Southern California, USA, is the largest and most ethnically diverse yet to be conducted into prostate cancer.
The findings, published in the latest edition of Nature Genetics, show a genetic basis for the increased risk of the disease among black men than in other racial groups and could be used to identify men who need targeted and earlier screening.
The international team of researchers pooled data from 17 large-scale studies from around the world and analysed the genetics of more than 200,000 men of European, African, Asian and Hispanic ancestry.
They compared men with and without prostate cancer and identified 86 new genetic variations that influence the risk of developing the disease, bringing the number of genetic changes associated with prostate cancer to 269.
Although the inherited genetic variants each has a small effect on the risk of developing prostate cancer, when many are combined the risk can increase substantially and following this study, the team say they believe the changes they have identified are part of the reason for the racial disparities.
The team developed an overall genetic risk score to help identify men who have the highest levels of inherited risk and when the score was applied to different ethnic and racial groups, black men were found to have average genetic risk score twice as high as white men of European ancestry. Asian men had about three quarters of the risk of white men.
They also found that the impact of common genetic variations on prostate cancer risk was greater for early-onset disease, suggesting that screening should begin even earlier than age 55 for men at high genetic risk.
Study co-leader Ros Eeles, professor of oncogenetics at The Institute of Cancer Research, London, and consultant in clinical oncology and oncogenetics at The Royal Marsden NHS Foundation Trust, said: “In our new study, we’ve shown that genetic factors underlie racial and ethnic differences in the incidence of prostate cancer – and by testing for a range of genetic changes, we can identify men of African ancestry who may be at high risk and could benefit from screening.
“Our findings greatly improve our understanding of genetic risk in men of African ancestry and could help guide and transform screening strategies, so that prostate cancer in men at high risk can be caught as early as possible.”
Study co-leader Christopher Haiman, professor of preventive medicine at the Keck School of Medicine and director of the Center for Genetic Epidemiology at the University of Southern California, said: “Through this large multiethnic analysis, we not only found new markers of risk, but also demonstrated that, by combining genetic information across diverse populations, we were able to identify a risk profile that can be applied across populations. This emphasises the enormous value of including multiple racial and ethnic populations into genetic studies.”
Nature Genetics 4 January 2020
Leave a Reply