International effort identifies ovarian cancer risk genes

An international study led by QIMR Berghofer and the University of Cambridge has found six new gene regions which increase a woman’s risk of ovarian cancer.

Head of QIMR Berghofer’s Cancer Program, Professor Georgia Chenevix-Trench said the project takes the number of ovarian cancer risk susceptibility regions identified from 12 to 18.

Professor Chenevix-Trench said incorporating these variants into testing to predict ovarian cancer risk would make any tool developed more precise.

“The variants or ‘typos’ identified have a more subtle impact than the BRCA1 and BRCA2 mutations,” Professor Chenevix-Trench said.

“Individually, each of these ‘typos’ increases the risk of cancer by a very small amount.

“However, if a woman carries a large number of these ‘typos’ her risk of developing ovarian cancer may be as high as that conferred by mutations in BRCA1 or 2.”

The study of almost 70,000 women drew on data from Ovarian Cancer Association Consortium (OCAC) and the Consortium of Investigators of BRCA1/2 (CIMBA).

The project involved hundreds of international collaborations from several consortia working on genotyping of hormone-related cancers, to generate sufficient statistical power to identify susceptibility and modifier genes.

QIMR Berghofer scientists are now part of an even bigger study which is likely to double the number of gene regions known to increase ovarian cancer risk.

“Once we identify each of these genetic ‘typos’, the next challenge is to find out the way they work – both individually and together,” Professor Chenevix-Trench said.

“Understanding how each of these variants works will eventually lead to an understanding how ovarian cancer develops, and how to develop better reduction medications and treatments.”

The study has been published in Nature Genetics: http://www.nature.com/ng/journal/vaop/ncurrent/full/ng.3185.html