Five new genetic variants have been discovered which, in combination, raise the risk of developing breast cancer by 16 per cent, according to a new study in Nature Genetics.
Scientists compared DNA samples from 3,659 women with breast cancer and a family history of the disease, against DNA from 4,897 unaffected controls. The study found that 1.2 per cent of familial breast cancer risk can be explained by these five new variants located on chromosomes nine, 10 and 11. Gene variants previously linked to breast cancer, including BRCA1 and BRCA2, were also found to increase risk.
Lead author of the study, Dr Douglas Easton, said: 'We know for sure that these gene variations are associated with risk. It is not the whole picture but it will contribute ultimately to genetic profiling of risk. It also contributes to our understanding of why the disease develops and will lead to a better understanding of the biology of the disease'.
Dr Helen George, head of science information at Cancer Research UK, said: 'This is by far the largest study of its kind to explore the common genetic variations that contribute to breast cancer risk. This research takes us a step closer to developing a powerful genetic test for the disease. Such a test could help doctors identify women who have an increased risk so that they can make informed decisions about how to take steps to reduce their chance of developing the disease'.
There are now 18 common genetic variations known to be linked to a small increased family risk of breast cancer, according to the study. These variations are thought to account for around eight per cent of inherited cases of breast cancer. Rarer mutations, which are known to confer a high and moderate risk of breast cancer, explain a further 20 per cent of familial risk.
The genetics of breast cancer are complex and further studies are required to determine what other genetic factors contribute to risk, according to NHS Choices.
The NHS says having these variants does not mean a person will definitely develop the disease, only that their likelihood is increased. Additional significant risk factors include age and post-menopausal obesity.
Almost 46,000 women and 300 men are diagnosed with breast cancer each year in the UK, according to the charity Breakthrough Breast Cancer.
The research was conducted at the Institute of Cancer Research in Surrey and additional institutions within the UK and the Netherlands.
Sources and References
Related Articles
Unwrapping the mystery behind BRCA1
Researchers based in the USA and the Netherlands report study findings that may explain why women with mutations in the BRCA1 gene are more susceptible to breast and ovarian cancer...
Study finds key genes involved in aggressive form of breast cancer
Scientists have identified a set of 15 genes that are associated with triple-negative breast cancer (TNBC), an aggressive form of the disease that does not respond to the drugs commonly used to treat other types of breast cancer...
Genetic test for cancer may reduce need for screening
Screening for breast and prostate cancer based on genetic risk factors as well as age could reduce the number of people screened without a significant reduction in the number of cancers detected, a new study suggests....
Small number of cancers may be caused by 'one-off onslaught', study suggests
UK scientists have shown that a single, catastrophic event can induce multiple cancer-causing mutations, simultaneously. The event was first discovered when analysing the genome of a leukaemia patient and subsequently detected in a range of other cancers...
Researchers discover 'oncogene addiction' in cancer
Researchers at Yale have identified a potential therapeutic target for cancer in the form of a micro RNA (miRNA) gene that cancer cells, but not normal cells, are dependent on for survival. Inactivating the miRNA causes cancer cell death and tumour regression....
Breast cancer linked to grandmother's diet
Rats fed on high-fat diets increased the chances of their daughters and granddaughters developing breast cancer, a US study has found...
Genetic information doesn't improve breast cancer risk prediction, large study finds
Breast cancer risk prediction does not improve significantly when genetic information is included in the risk prediction model, a new study published in the New England Journal of Medicine has found....
Genetic test to improve breast cancer treatment
Scientists have developed a way to identify six key genes which, if faulty, can prevent particular chemotherapy drugs from working in patients with breast cancer. The findings bring cancer therapy one step closer to the promise of targeted treatments for patients, based on the genetic characteristics of their tumours....
Genetic susceptibility to common complex disorders
As our understanding of genetics and associated disorders has developed, many genetic tests performing functions - from predicting certain genetic predispositions and identifying rare monogenetic disorders, to ancestry and other 'novelty' tests - have been introduced to the healthcare market. Many geneticists are concerned about the regulation of these tests, which are performed by the NHS, the private sector, or distributed directly to consumers. Experts are calling for more transparent eval...
Leave a Reply
You must be logged in to post a comment.