Scientists have found a possible link between a newly-discovered virus and breast cancer.
Breast cancer affects one in nine British women
Doctors in Australia discovered the virus in 40% of tissue samples taken from women with the disease.
Further tests showed that only 2% of women without the disease carry this virus, which is called HHMMTV.
While further research is needed, they hope the discovery could lead to new treatments to fight breast cancer. It affects one in nine British women.
The scientists, from Sydney's University of New South Wales and
Prince of Wales Hospital, found evidence to suggest that many men who develop breast cancer may also carry this virus.
They identified the virus in 50% of the male breast cancer tissues they tested.
The scientists believe the virus may be the human form of the mammary tumour virus. This causes 95% of breast cancer in mice.
While it is too early to suggest that this virus may cause breast cancer, the researchers said they were excited by the finding.
Caroline Ford, who led the study, said the discovery could lead to new treatments for the disease if a link can be proven.
"Many people believe that breast cancer is purely a hereditary
disease, yet hereditary breast cancer is estimated to account for
only 5% of all cases of breast cancer," she said.
"In other words, we have little idea what causes 19 out of 20
"Our preliminary research indicates that a virus may be
"This new research supports the link between this virus and
breast cancer in Australia.
"If it can be shown that this virus causes cancer, the possibility of a preventative vaccine for breast cancer would be of enormous consequence," she said.
"It's an exciting discovery, but there's a lot of work still to do to get sufficient proof of the role of the virus."
The study is published in the Journal of Clinical
The findings were presented at Australia's Fresh Science Forum, which is part of the government sponsored Science Week.