From Nature:
Breast cancer — which will affect about one in every nine women in Britain and the United States — is known to have a strong genetic influence. But until now, known genes could account for only about a quarter of the genetic component of cancer risk. To search for some of the many other genes thought to make small differences to a woman’s breast-cancer risk, Easton and his colleagues compared the genomes of some 4,400 women with breast cancer with those of about 4,300 who did not have the disease.
They identified 30 differences in single DNA bases that seemed to be linked to the disease. These were then compared in more than 20,000 women with breast cancer and in a similar number of controls. The results are reported in Nature. Three of the newly discovered genes are involved in controlling the growth of cells. The gene with the strongest association was fibroblast growth factor receptor 2, or FGFR2. Women who have two copies of the high-risk version of this gene — about 16% of the population — have a 60% greater chance of developing breast cancer than do those with no copies of the gene, Easton and his colleagues found.
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