Newly Identified Genetic Variations May Help Screen for Cancers

U.K. scientists have found more than 80 new genetic variations linked to increased risk of developing cancer, which may eventually help with screening tests to warn of the disease at an earlier stage.

While each alteration raises the risk of cancer by a small amount, those who carry a combination of them could see their risk of developing prostate cancer increase by almost 50 percent and breast cancer by 30 percent, according to scientists at the University of Cambridge and The Institute of Cancer Research, London.

The new research increases understanding of genetic risk factors that are linked to more than half of all cancers, with the rest caused by lifestyle factors. It may also pave the way for gene-based screening tests using saliva samples, according to Paul Pharoah, cancer epidemiologist at the University of Cambridge.

“We’re on the verge of being able to use our knowledge of these genetic variations to develop tests that could complement breast cancer screening and take us a step closer to having an effective prostate cancer screening program,” Doug Easton, professor of genetic epidemiology at Cambridge, said in a statement today.

The research, detailed in a series of papers published by Nature Genetics and the American Journal of Human Genetics, among other journals, studied the DNA make-up of more than 100,000 people with cancer and 100,000 people from the general population.

Lifestyle Factors

The genetic variations, called single nucleotide polymorphisms, are all inherited and are not formed by environmental factors, Easton said. Risks associated with these variations can be multiplied by lifestyle factors, which are equally important in the development of cancers, he said.

“They are two things that go together,” Easton told reporters at a briefing in London.

While the low cost of gene-based screening tests could help to identify cancer risks earlier, they may raise ethical questions for patients for whom knowledge of the risk could lead to decisions on such things as preventive masectomies, Pharoah said.

Still, this improved understanding has the potential to dramatically reduce deaths from cancers, said Ros Eeles, professor of oncogenetics at The Institute of Cancer Research.

In the case of prostate cancer, “if we can show from further studies that such men benefit from regular screening, we could have a big impact on the number of people dying from the disease, which is still far too high,” she said.

The research was funded by Cancer Research U.K. and the Wellcome Trust.

Before it's here, it's on the Bloomberg Terminal.