Gene variant linked to male breast cancer
An inherited gene variant that increases a man's chance of developing breast cancer by up to 50 per cent has been identified by an international team of scientists.
The finding suggests that the causes of the disease may differ between women and men.
The result comes as part of the worlds largest ever study of male breast cancer, in which researchers analysed the genetic code of 823 male breast cancer patients for genetic variants called 'single nucleotide polymorphisms' (SNPs). They wanted to find SNPs that are more common in men with the disease.
While male breast cancer has a much lower public profile than its female counterpart, around 350 men are diagnosed with the disease in the UK each year
Scientists have previously shown that mutations in the BRCA2 gene are involved in around one in 10 male breast cancers. But one of the strongest risk factors for the disease is having a male family member with the disease. So researchers have long suspected that other inherited genetic factors may be involved.
The researchers found that a specific variation in the RAD51B gene could be even more significant than BRCA2, increasing a man's chances of developing breast cancer by up to half.
RAD51B, like BRCA2, helps repair damaged DNA inside cells. Changes RAD51B have been previously linked to women's risk of breast cancer, but the new variant is in a different part of the gene to the 'female' version.
Dr Nick Orr, from the Breakthrough Breast Cancer Research Centre at The Institute of Cancer Research in London, who led the research, said it was a "leap forward" in the understanding of male breast cancer.
"[This] shows that while there are similarities with female breast cancer, the causes of the disease can work differently in men. This raises the possibility of different ways to treat the disease specifically for men," he added.
Henry Scowcroft, science information manager at Cancer Research UK, said: "It's starting to emerge that the genetic triggers of breast cancer vary between men and women. For example, men who inherit a damaged BRCA2 breast cancer gene have a higher risk of developing breast cancer than women with similar faulty genes, and those with a male family member who had breast cancer are also at much higher risk. This suggests there are probably differences between the sexes in how the disease develops, and how best to treat it.
"Researchers have been hunting for genes involved in male breast cancer and this new study identifies several regions in our genetic material that can influence a man's risk. This research should spur further efforts to understand how breast cancer arises in men, and ultimately more effective treatments for them."
The study is published in the journal Nature Genetics.
Copyright Press Association 2012