Irish researchers help identify genes which can predict breast cancer 

Irish researchers and patients were part of a new study which has identified genes which predict breast cancer, allowing for early treatment. Picture: file

A breakthrough study has identified nine genes which are predictors for breast cancer, meaning that at-risk women can get help earlier than at present.

The study, published in  The New England Journal of Medicine, involved analysis of more than 113,000 women worldwide including 2,000 Irish women working with researchers at the National University of Galway.

Breast cancer is the most common cause of death among middle-aged women, said Professor Michael Kerin, the research director of the National Breast Cancer Research Institute based in NUI Galway.

“This study is of practical importance,” he said. 

“We can identify the members within families who have abnormal genes that puts them at a higher risk of getting breast cancer, and they can avail of strategies such as early screening and risk-reduction surgery, in order to improve their life expectancy.”

Prof Kerin said this study shows there are nine genes associated with breast cancer risk, four of which are associated with quite a high risk.

He expects the findings to be used in medical consultations in Ireland relatively shortly. And said women do not need to request any extra tests as doctors will discuss their family history as part of initial consultations.

Prof Kerin, who is also director of the cancer MCAN (managed clinical academic network) for Saolta University Health Care Group, said: “When you get in some families as we do all the time, a woman might say, 'my granny had breast cancer, my mother had breast cancer. I’m now 25 or 30 years of age, what do I need to do?' The information around these genes will give women more options for earlier treatment.

Prof Michael Kerin hailed the practical use of the international research, the Irish leg of which studied the DNA of 2,000 women through the National Breast Cancer Research Institute in NUIG.   Picture: Kelvin Gilmor

“We can identify people within the family, some of them don’t have the bad gene, and some of them do. For the ones who do have the bad gene, we can then put a structured approach in place with mammography and MRI scanning of the breast in women from 25 or so,” he said.

The study builds on previous work done on two already known cancer genes, BRCA1 and BRCA2. Led from the University of Cambridge, the Bridges (Breast Cancer Risk after Diagnostic Gene Sequencing) study aimed to develop gene panel testing for the prediction of breast cancer risk.

“The Bridges study has revealed that changes which were thought to be unimportant in the well-known breast cancer genes, BRCA1 and BRCA2, are significant,” Prof Kerin said.

“This allows us to manage the risk of developing breast cancer in people affected by these gene alterations.” 

The Irish leg of the study was run through the Breast Cancer in Galway Genetics Study, directed since 2008 by Prof Kerin and Dr Nicola Miller, a lecturer at NUI Galway’s School of Medicine.

DNA samples collected between 2001 and 2008 from 1,000 Irish patients and 1,000 women acting as a control contributed to the findings of the global study. These samples also added insight to other studies.

Dr Miller said: “While we can’t change the genes we inherit, this knowledge will benefit patients undergoing genetic testing for breast cancer susceptibility.” 

She also highlighted the importance of funding research like this.

One in nine Irish women will be affected by breast cancer, Breast Cancer Ireland has said. About 3,100 new cases are diagnosed annually.

The survival rate has improved to 85% due to research and treatment breakthroughs. 

The published study is available online in The New England Journal of Medicine.