Four variations in a woman's genetic code could put her at a higher risk for ovarian cancer, a new study suggests.
Screening for these particular variations – which occur in about 20 percent of all women – could be vital for prevention and early detection of ovarian cancer, said study researcher Ellen Goode, an epidemiologist at the Mayo Clinic and part of the Ovarian Cancer Association Consortium.
"Eventually, a woman can go to the clinic and, if she has family history, might be given a series of genetic tests to look at these and other changes" to determine if she's at a higher risk for ovarian cancer, Goode told MyHealthNewsDaily.
Ovarian cancer is the eighth most common cancer among women in the United States, and is the fifth leading cause of cancer deaths , according to Centers for Disease Control and Prevention.
The cancer is notoriously difficult to detect in its early stages before it has spread to other organs, but early detection bumps the five-year survival rate to 93 percent, according to the Mayo Clinic.
If women knew their risk, they could get screened earlier for the cancer and take preventive action, Goode said. For example, if a woman knew she was at high risk, she might decide to have her ovaries removed as a precautionary measure.
In the study, scientists from around the world examined the genes of nearly 24,000 women to find genetic variations – called single-nucleotide polymorphisms – that are associated with cancer risk.
The researchers found four genetic variations that were associated with a high risk for ovarian cancer. Having all four meant a higher risk than just having one variation, Goode said.
"An important thing with this type of study is it's not saying you have a 100 percent chance that you will get ovarian cancer if you have changes, but you might have a slightly higher risk," she said. There are other genes – such as the BRCA1 and BRCA2 genes – that are associated with a much higher risk of cancer.
But the findings are further evidence that ovarian cancer is hereditary, Goode said.
"If you have a family history of ovarian cancer, you have a twofold chance of having it, too," she said. "Now we're learning more about why."
Previous studies have found variations on two other chromosomes that could also raise the risk of ovarian cancer , she added.
Next, researchers want to look for even rarer gene variations that could also be risk factors for ovarian cancer, Goode said, as well as gene variations that may not be associated with as high a risk, but are still suspect.
Scientists are also still trying to figure out why these particular variations lead to a high risk of ovarian cancer in the first place.
They also plan to look at environmental and lifestyle factors that could play a part in lowering cancer risk, such as oral contraceptives, she said.
The study was published today (Sept. 19) in the journal Nature Genetics.