Researchers in Hong Kong have found a genetic mutation that they believe is linked with a high risk of breast cancer. They believe the discovery could be important enough to be included in genetic screening for women of Chinese origin.
Dr Ava Kwong, the Assistant Dean and Clinical Associate Professor at the University of Hong Kong and Director of the Hong Kong Hereditary and High Risk Breast and Ovarian Cancer Programme, told the 10th European Breast Cancer Conference that the mutation appears to be associated with a high risk of breast cancer risk in some members of the ethnic Chinese population.
Dr Kwong’s team tested over 1,100 patients with a family history of breast cancer and they all tested negative for four of the most common breast cancer-causing mutations: BRCA1, BRCA2, TP53, and PTEN.
“We decided to test for the RECQL mutation, recently identified as being associated with an increased risk of the disease,” she said “We found that RECQL was present in 0.54% of the women in our group (Southern Chinese), and we also know that a similar group of Northern Chinese women, from Beijing, had a RECQL incidence of 2%.”
“We need to do further work in order to be able to understand whether we are looking at founder mutations, which occur in the DNA of one or more individuals who were founders of a distinct population, since even within the two Chinese groups two RECQL mutation loci, or specific positions on a chromosome, were seen more than once in different families” said Dr Kwong.
“We hope that our work will enable screening programmes for high risk women to be better targeted and also lead to the development of new drugs aimed exclusively at patients carrying specific mutations,” said Dr Kwong.
Meanwhile the same conference has also heard from the leader of a major study in Denmark that appears to disprove the commonly held belief that there is a link between exercise and breast density.
Women with a higher breast density have a higher risk of developing cancer and exercise is known to protect against the disease. However the Danish team found no link between physical activity and breast density, and believe that the protective effect of physical activity on breast cancer must be through other mechanisms.
This finding from a study of 5,700 was unexpected because it was always believed that reducing BMI and fatty tissue would increase breast density.
The team are interested to see if larger studies replicate their own findings.