New genes linked to breast cancer

REYKJAVIK, Iceland, April 28 (UPI) -- Scientists in Iceland said they have found a fourth set of genetic variants linked to an increased risk of estrogen receptor-positive breast cancer.

The findings, published in the journal Nature genetics, are being used to develop a DNA test to identify women who should be closely screened at an early age for the disease, the biopharmaceutical company deCode Genetics said Sunday in a release.

The test is expected to be released later this year, the company's report said.

Researchers reported the discovery of two common single-letter variants on chromosome 5 of the human genome that are associated with risk of estrogen receptor-positive breast cancer. They said more than 60 percent of the general population carries at least one copy of the risk variant rs4415084. Women who have inherited the variant from both parents are at approximately 50 percent greater risk of developing ER+ breast cancer than women who have not inherited the variant, the report said.

The second variant occurs only in tandem with the first, adding slight risk of the disease. The variants are estimated to account for about 11 percent of breast cancers overall.