Scientists identify four new breast cancer risk genes

New Delhi: Scientists have found at least four new genes associated with breast cancer that may help identify women at increased risk of the disease.

The finding, published recently in the journal Nature Genetics, also provides crucial information on the biological mechanisms underlying cancer development, potentially opening the way to identifying new treatments.

The international team led by researchers at the University of Cambridge in the UK and Universite Laval, Canada noted that current genetic tests for breast cancer only consider a few genes, such as BRCA1, BRCA2, and PALB2.

However, these only explain a minority of the genetic risk, suggesting that more genes remain to be identified, they said.

The latest study looked at genetic changes in all genes in 26,000 women with breast cancer and 217,000 (2.17 lakh) women without breast cancer, from eight countries in Europe and Asia.

"To our knowledge, this is the largest study of its kind," said Professor Douglas Easton, from the University of Cambridge, who co-led the study.

"It was made possible through the use of data from multiple collaborators in many countries, as well as publicly available data from the UK Biobank," Easton said in a statement.

The researchers found evidence for at least four new breast cancer risk genes, with suggestive evidence for many others.

Identification of these new genes will contribute to the understanding of the genetic risk of breast cancer and help improve risk prediction by better identifying those women at higher risk of the disease, they said.

The findings will better inform approaches to breast screening, risk reduction and clinical management, according to the researchers.

The aim is to integrate this information into a comprehensive risk prediction tool currently used worldwide by health professionals, they said.

"Improving genetic counselling for high-risk women will promote shared decision-making regarding risk reduction strategies, screening and determination of treatment options," said Professor Jacques Simard of Universita Laval, co-lead of the study.

"Although most of the variants identified in these new genes are rare, the risks can be significant for women who carry them. For example, alterations in one of the new genes, MAP3K1, appear to give rise to a particularly high risk of breast cancer,” Simard said.

Before this information can be used in a clinical setting, scientists need to validate the results in further datasets.

"We need additional data to determine more precisely the risks of cancer associated with variants in these genes, to study the characteristics of the tumours, and to understand how these genetic effects combine with other lifestyle factors affecting breast cancer risks," Easton added.