New tests and treatments for prostate cancer could be on the horizon after the discovery of genetic code variants that triple the chances of developing the disease.
Scientists screened the DNA of tens of thousands of men to identify the nine previously unknown risk areas.
The research highlighted at least two genes that could be targets for new treatments.
One, known as NKX3.1, helps control how cells die and may have a key role in cancer.
Drugs that could help men with a defective NKX3.1 gene are already in clinical trials.
Another gene called ITGA6 that is important for cell growth, movement and survival could also be a potential drug target. When overactive it is associated with some prostate cancers.
Prostate cancer affects around 35,000 men in the UK each year and kills just over 10,000.
The disease is the most common cancer in British men, accounting for a quarter of all new cases.
Four scientific papers on the genetic discoveries from different international teams were published in the journal Nature Genetics.
One group led by Dr Ros Eeles, from the Institute of Cancer Research in Sutton, Surrey, examined the DNA of 38,000 men and found seven regions in the genetic code that increased the risk of prostate cancer.
The scientists looked at differences in more than 43,000 single letter variations in the code called single nucleotide polymorphisms, or SNPs.
Dr Eeles, whose team was funded by the charity Cancer Research UK, said: “Our study adds further compelling evidence that genetic factors can influence a man’s risk of developing prostate cancer.
"These results will help us to more accurately calculate the risk that a man could develop prostate cancer which will enable more targeted screening. Understanding more about these genes could also lead to the development of new treatments.”
The research takes the total number of regions of the human genome – or genetic code blueprint – associated with a higher prostate cancer risk to more than 20.
Other findings focused on a region on chromosome eight – one of the packages of DNA that house the genes – which has previously been linked to prostate cancer.
Two new SNP risk variants were found at this location that independently raise the likelihood of developing the disease.
Scientists estimate that one in 100 men carrying most of the genetic variants have a one in five lifetime risk of prostate cancer. In comparison, the average odds of a man developing prostate cancer in his lifetime are one in 10.
Co-author Professor Doug Easton, director of Cancer Research UK’s Genetic Epidemiology Unit at Cambridge University, said: “Prostate cancer has the greatest number of independent genes affecting risk of any cancer but we still understand very little about how it develops. This study provides new clues about the processes involved, which could be used to aid the development of new treatments in the future.”
Cancer Research UK’s chief executive Harpal Kumar said: “This important research increases our knowledge of how some genes can affect men’s risk of developing prostate cancer. Thanks to international collaborations like this, funded by Cancer Research UK and others, we have been able to scan the DNA of thousands of men to discover more about the genes that affect prostate cancer risk.
“This is ground-breaking research that we hope will open up more avenues worldwide to diagnose, prevent and treat this disease better.”
Four of the newly identified markers are to be incorporated into a genetic screening test for prostate cancer marketed by the Icelandic company deCODE.
Scientists from deCODE were among those who took part in the research.
Kari Stefansson, the company’s chief executive, said: “Using our ability to put these SNPs in a population-wide context, we show that it is now possible to identify those at more than a 30% lifetime risk, independent of other standard risk factors such as age and family history.
“By incorporating this new, personalised gauge of susceptibility into our arsenal for improving prevention and early diagnosis, we can more effectively and accurately identify those men who would benefit most from intensive screening.”