Women who carry an inherited fault in the gene BRIP1 are over three times more likely to develop ovarian cancer than those without the fault, according to a study published in the Journal of the National Cancer Institute.
Around 18 women in every 1,000 develop ovarian cancer, but this risk increases to around 58 women in every 1,000 for women with a fault in the BRIP1 gene. It's estimated that one in every 1,000 UK women have the gene fault.
This is because faults in the gene mean the cell cannot properly repair its DNA, causing genetic damage to build up, leading to cancer.
The study, led by Cancer Research UK scientists from the University of Cambridge, UCL and Imperial College London, also showed that women who carried the BRIP1 gene mutation were more likely to be diagnosed with an aggressive cancer, at a later stage and tended to be diagnosed at an older age.
The researchers compared the genes of more than 8,000 white European women - including around 3,250 women diagnosed with ovarian cancer, 3,400 women who did not have cancer and 2,000 women who had a family history of the disease.
Professor Paul Pharoah, professor of cancer epidemiology at the Cancer Research UK Cambridge Institute, said: "Our work has found a valuable piece of the puzzle behind ovarian cancer and we hope that our work could eventually form the basis of a genetic test to identify women at greatest risk.
"Finding these women will help us prevent more cancers and save lives. This would be important in a disease like ovarian cancer, which tends to be diagnosed at a late stage when the chances of survival are worse."
Each year in the UK around 7,100 women are diagnosed with ovarian cancer and more than 4,200 women die from the disease.
Nell Barrie, Cancer Research UK's senior science information manager, said: "Research like this, which looks at inherited genetic changes and how they can affect a woman's risk, is vital. We urgently need ways to detect ovarian cancer early, as the cancer is often diagnosed when it's too late for effective treatment because the cancer has already spread. We hope this research will lead to a reliable way to spot women at a high risk, so they can be monitored to find any signs of the disease at an early stage."