BRCA gene mutations have been linked to cancers, including prostate and breast cancer in men, in the largest study to date.
Mutations on the breast cancer susceptibility genes, BRCA1 and BRCA2, are known to be linked to higher rates of breast and ovarian cancer. However, new research has shown that carriers of these mutations are also at a higher risk of other cancers, including pancreatic, prostate and stomach cancers. This study, published in the Journal of Clinical Oncology, used data from the families of over 5000 BRCA mutation carriers to estimate their increased cancer risk.
'These large datasets of patients have allowed us to estimate with much greater accuracy the extent to which faulty BRCA1 and BRCA2 genes increase the risk of several cancers' said Professor Antonis Antoniou from the Department of Public Health and Primary Care at the University of Cambridge, who led the study. 'We've known for some time that they're linked to breast and ovarian cancer, but there's been uncertainty about other cancers.'
The researchers analysed retrospectively the prevalence of 22 types of cancer in nearly 15,000 carriers of BRCA1 and BRCA2 mutations and over 9000 noncarriers. Patients were recruited from the Consortium of Investigators of Modifiers of BRCA1/2, from centres across Europe, North and South America, Australia and Asia. The researchers considered the rates of cancers in the carriers versus the non-carriers after adjusting for age, country and birth decade, and discovered that for seven of these cancers those with mutations in BRCA1 or BRCA2 were significantly more at risk.
In particular, male carriers of BRCA2 mutations were found to be more than twice as likely to develop prostate cancer than non-carriers, with 27 percent developing prostate cancer by the age of 80. Additionally, male carriers of BRCA1 and BRCA2 mutations are four and 44 times more likely to get breast cancer than non-carriers respectively. The study found that nearly 4 in every 100 male BRCA2 mutations carriers will develop breast cancer by the age of 80.
Pancreatic cancer was also found to be between two and three times more common in carriers of mutations on the BRCA gene regardless of gender. Stomach cancer was also linked to BRCA mutation carriers, with BRCA1 carriers being two times more at risk than non-carriers. Out of 1000 BRCA2 carriers, this study found that 35 develop stomach cancer before the age of 80 regardless of gender.
Mutations on the BRCA gene affect one in between 300 and 400 people, but this rate is higher in some ethnic groups. Michelle Mitchell, the chief executive of Cancer Research UK explained: 'Cancers caused by inherited faulty BRCA genes are relatively rare, and other factors like age, smoking, diet and other preventable factors contribute to a person's risk. Improving our understanding of how faults in our genes are associated with certain cancers puts us in a much better position to pinpoint those at a higher risk of developing cancer'.
Sources and References
-
Faulty BRCA genes linked to prostate and pancreatic cancers
-
Cancer risks associated with BRCA1 and BRCA2 pathogenic variants
-
Faulty BRCA genes, known to increase breast cancer risk, now linked to prostate and pancreatic cancers
-
Jolie gene' linked to more cancers
-
What men need to know about the 'Jolie gene' and other cancers
Leave a Reply
You must be logged in to post a comment.