Research summary
December 2007
New gene linked to breast cancer
Summary
Researchers in a multicentre international study have discovered a new gene, HMMR that, if mutated, may increase a woman’s risk of developing breast cancer. The study was published in the journal Nature Genetics (November 2007).
The HMMR mutation is found in about 10 per cent of the population. By comparison, inherited mutations in the two main genes known to be involved in the development of breast cancer, BRCA1 and BRCA2, are found in less than one per cent of the population. The HMMR gene was found to interact with BRCA1.
The researchers found women with one copy of an HMMR mutation had a 23 per cent increased risk of developing breast cancer compared to women who did not have the mutation. Those women who inherited two copies of a gene mutation were at 46 per cent increased risk, though this is rare. Additionally, those women with the HMMR mutation who did develop breast cancer, did so an average of 12 months younger than the women without the mutation. The researchers believe HMMR may be linked to early-onset breast cancer.
National Breast Cancer Centre comment
The discovery of another gene which, if mutated, may be involved in the development of breast cancer is important. It helps to build a more complete picture of what puts a person at increased risk of the disease. This may have implications for the early detection and treatment of breast cancer.
The discovery also helps us to understand why there are so many variations in families who carry a BRCA1 gene mutation – why one carrier develops breast cancer at a young age and another may not develop breast cancer until they are older or not at all. This indicates there are other genetic, lifestyle or environmental factors that influence the development of breast cancer.
Such research may help to more accurately estimate an individual’s risk of developing breast cancer.