New test predicts the risk of non-hereditary breast cancer

A simple blood test is currently in development that could help predict the likelihood of a woman developing breast cancer, even in the absence of a high-risk BRCA1 gene mutation, according to new UCL research. The research, published in Genome Medicine, identifies an epigenetic signature in the blood of women predisposed for breast cancer owing to an inherited genetic mutation of the BRCA1 gene. Epigenetic alterations are thought to be key molecular switches that are involved in the development of cancer. Strikingly, the same signature was discovered in the blood of women without a BRCA1 mutation but who went on to develop breast cancer, making it a potential early marker of women's cancer in the general population. BRCA1 mutation is inherited from a parent, and is the cause of at least ten percent of breast cancers. The cause of the remaining 90% of sporadic breast cancers in non-mutation carriers remains to be explained. Scientists are beginning to understand that genetic mutations are not the sole contributors to disease development and that the way in which genes are arranged in our cells can affect whether they function appropriately - that is, whether they are turned on or off.