Researchers have identified a genetic marker in the blood that could indicate whether a woman will develop breast cancer.
The study out of University College London looked at blood samples taken from women years before they developed breast cancer.
Researchers looked at their DNA, and whether they had a genetic signature that predisposed them to the disease like the BRCA1 gene.
They found a specific genetic signature present in women with and without the BRCA1 gene who went on to develop the disease.
They say this could be an early marker of breast cancer in women who do not have the BRCA mutation.