Study Calls for Broader Testing for Cancer Risk Genes

BRCA mutations may put women at about an 80% risk of developing breast cancer. The BBC reports on a new study by researchers based at University College London and the University of Manchester which says that women who are at high risk should undergo DNA testing for breast cancer risk genes. The findings of the study published in the Journal of the National Cancer Institute show that wider cancer screening of women at increased risk of cancer could save lives and money.

The American Cancer Society states that the most common cause of hereditary breast cancer is an inherited mutation in the BRCA1 and BRCA2 genes. BRCA gene mutations that women inherit account for about 5 percent of breast cancers and about 10 to 15 percent of ovarian cancers. In normal cells, these genes produce proteins that keep the cells from growing abnormally, thereby helping to prevent cancer. BRCA gene mutations prevent DNA from repairing itself and increase the risks of cancer. Women who inherit a mutated copy of either gene from a parent stand a high risk of developing breast cancer during their lifetime. Inherited gene mutations are also linked to ovarian and prostate cancer.

The researchers evaluated 1,034 Ashkenazi Jewish women in the U.K., who are at high risk in a clinical trial funded by a charity. The effectiveness of screening all Ashkenazi Jews was compared with screening only those who were designated as being at high risk due to genetic factors. It was found that 56% of those carrying a mutation would not have had a BRCA gene test based on family history alone. In the U.S., BRCA mutations are more common among Ashkenazi Jews than in other racial and ethnic groups, though they can occur in anyone.

Medical laboratories offer various types of blood tests to detect cancer cells, proteins or other substances made by the cancer. These tests, performed using high quality laboratory equipment and reagents, include complete blood count (CBC), blood protein testing, tumor marker tests, and circulating tumor cell tests. The availability of such tests goes a long way in helping in early and broader genetic testing for cancer risk genes.