UK scientists have identified a further gene which increases a woman's risk of developing breast cancer. An international study of 20,000 women found having a faulty version of the CHEK2 gene doubles their cancer risk.
UK women have a one in nine chance of developing breast cancer. Carrying CHEK2 increases that to one in four.
The American Journal of Human Genetics study said the findings brought a comprehensive genetic test of breast cancer risk a step closer. Women can already be tested to see if they have inherited these genes, reports BBC.
According to medicalnewstoday.com Women in the general population in the UK have a one in nine chance of developing breast cancer at some point in their lifetime. Carrying CHEK2*1100delC would increase this risk to about one in four. CHEK2 is the first confirmed 'low risk' gene. Scientists believe a number more exist, each pushing up the risk of breast cancer to a moderate degree.
The data suggest the increase in risk was greater for women diagnosed at a younger age. Hereditary factors are generally more important in cancers that occur in younger women.
Professor Easton adds: "This is perhaps the largest study of its kind. It is the most reliable method for calculating the impact of potential breast cancer genes, and is also being applied to other types of cancer."
The taller a woman is, the greater her risk of developing breast cancer after menopause, a new European study says.
The research also sheds light on the link between obesity and breast cancer. It reveals that the greater a woman's percentage of body fat, the greater her risk of developing cancer. Previously, it was believed that abdominal fat was a more precise indication of breast cancer risk, as it is with cardiovascular risk.
Published today in the International Journal of Cancer, the study also confirms that hormone replacement therapy increases the risk of developing breast cancer for post-menopausal women, informs theglobeandmail.com