Scientists have identified a gene which, when mutated, can increase a woman's chances of developing breast cancer by over a third.
Using computer modelling, the team of international researchers found that the gene, HMMR, interacts with the well-known breast cancer gene BRCA1.
Like BRCA1, HMMR can cause genetic instability if altered, potentially leading to out-of-control cell division and the development of cancer.
The scientists hope the discovery of the pathway will lead to the development of new treatments.
Study author Dr Laura Rozek said: "Identifying genes involved in cancer in the general population is important, because not all of the causes of breast cancer have been found."
She added: "Through discoveries such as this, someday we might be able to more precisely estimate a person's risk of cancer based on their genes."
The study can be viewed in the advance online edition of Nature Genetics.
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