Research summary
July 2007
Four new breast cancer genes discovered
Summary
An international study involving more than 50,000 women has discovered four new gene variants found to increase a woman’s risk of developing breast cancer. The study was published in the journal Nature (online 27 May 2007).
Variants of the four genes – FGFR2, TNRC9, MAP3K1 and LSP1 – are more commonly found in the population than the BRCA1 and BRCA2 gene variants. However, the new genes are associated with a much lower risk of breast cancer than BRCA1 and BRCA2.
The researchers estimate those people who have a variant in one of the newly discovered genes will have a 10 to 30 per cent increased risk of breast cancer. The BRCA1 and BRCA2 genetic variants increase a woman’s risk of developing breast cancer by about 40 to 80 per cent.
The researchers believe that up to 200 genes may be involved in the development of breast cancer and they expect to discover another 50 genes in the next two years.
National Breast Cancer Centre comment
The discovery of the high-risk BRCA1 and BRCA2 genes ten years ago was a significant breakthrough in breast cancer research. The discovery of an additional four gene variants adds further to our understanding of the role genetics plays in the development of breast cancer. It may help to explain the incidence of breast cancer that occurs as a pattern within families that do not have the BRCA1 or BRCA2 mutation.
However, as each of the new gene variants is only associated with a small increase in breast cancer risk, they only become significant for an individual woman if she is carrying a number of variants.
The significance of this research is that researchers now understand how to find these genes and can direct more scientific research into what these genes do and how they interact with each other. The methods used to discover these gene variants can also be applied to uncover more genes involved in the development of breast and other cancers.
It is anticipated that this research may have implications in the future for the way women are screened for breast cancer. The discovery of many more gene variants may enable the development of a blood screening test that will identify women at increased risk of breast cancer due to genetic factors. Such women may undergo more frequent surveillance or undertake other preventative activities.