Scientists now have a better understanding of the inherited risk of prostate cancer, after an international study identified 23 new genetic variants (changes in the DNA sequence) associated with increased risk of the disease.
The study, partly funded by Prostate Cancer UK, brings the total number of common genetic variants linked to prostate cancer to 100. And testing for them can identify the one per cent of men of European ancestry whose risk of prostate cancer is six times higher than the population average, or the ten per cent whose risk is three times higher.
Although the researchers had more samples from men of European ancestry, they also used samples from men of African, Japanese and Latino heritage. This helped to increase the statistical significance of their results and increase their chances of finding new genetic changes.
Unlike some of the major genes like BRCA1 or BRCA2 that can have a big impact on a man’s risk of developing prostate cancer, but are relatively rare, the genetic variants identified in this, and earlier studies, occur commonly in the population. The difference is that individually, these DNA changes may not have much effect on a man’s chance of getting prostate cancer, but when combined with other common changes, his risk might increase significantly.
The research was published in Nature Genetics and was funded in equal amounts by Cancer Research UK, Prostate Cancer UK, the EU and the National Institutes of Health in the US.
Dr Matthew Hobbs, Deputy Director of Research at Prostate Cancer UK said: “There’s no doubt that genetic testing for prostate cancer is an exciting area of research. The results of this study could take us a step closer to targeted screening by allowing us to identify those most at risk of the disease based on the genes that they possess. However, this is not the end of the story and the challenge now lies in translating this knowledge into a reliable test that can be used on a large scale through the NHS to find those men at highest risk.
“It is also absolutely vital that researchers build on this work to discover which of these genetic variants can tell us whether a man’s cancer is aggressive and likely to go on to kill him, or one that may never cause any harm. This would save those men with non-aggressive disease from undergoing unnecessary treatment.”