AUSTRALIAN researchers have found a link between breast cancer and dense breast tissue, which shows up during mammograms.

In a world first, researchers at the University of Melbourne discovered two genetic variants associated with breast cancer, which also influenced the density of breast tissue.

The researchers had long suspected a connection but found the variants when they studied more than 2000 women's mammograms and DNA from blood samples.

John Hopper, from the university's school of population health, said the finding could help identify women at higher risk of breast cancer.

The research, published in Cancer Research, could also help explain the biological causes of the disease, which helps the search for a cure.

''This is the beginning of a new research focus on how cancer begins and the role mammographic density plays,'' he said.

Professor Hopper said there was nothing women could do to act on the research at this stage because it was impossible to tell how dense the breast tissue was by feeling or looking at breasts. Density could be examined only with the help of a mammogram.

The chief executive of BreastScreen Victoria, Vicki Pridmore, said the research would not change the advice to women about screening or the way mammograms were done.

She said women aged 50 to 69 should have a mammogram every two years. These were funded by the state and federal governments. The service was also open to women aged 40 to 49 and those over 70.

Breast cancer is the most common cause of cancer-related death in Australian women. About one in 11 women will be diagnosed with it before 75.

http://www.smh.com.au/national/scientists-find-link-between-breast-cancer-and-dense-tissue-20100216-o8zg.html