A team of international scientists, including from the Queensland Institute of Medical Research (QIMR), have identified more than 60 regions of the human genome that can significantly increase a person’s risk of breast, prostate and ovarian cancer.

Head of QIMR’s Cancer Program, Professor Georgia Chenevix-Trench, said that the study of over 200,000 people worldwide could result in breakthrough new treatments, targeted screening and greater understanding of how cancers develop.

“QIMR has played a major role in research with enormous consequences,” Professor Chenevix-Trench said. 

“We’ve gone beyond gene discovery to now having a much better understanding of how these cancer genes function. This is a major step forward in the battle to find new treatments.”

The research, which was led by Cambridge University was looking for single nucleotide polymorphisms (SNPs) that flag the presence of nearby genes, or genetic ‘”switches”, which may increase the risk of developing cancer.

By studying the DNA makeup of more than 100,000 people with cancer and 100,000 without, the scientists found “typos” which were more common in people with breast, prostate or ovarian cancers. 

“By themselves, each of these typos increases the risk of cancer by a very small amount,” Professor Chenevix-Trench said. 

“But the small number of women in the population who have a large number of them are three times more likely to develop breast cancer than the women who carry an average number of typos.” 

For breast cancer, the researchers found 49 SNPs, more than doubling the number found in previous studies. They were found in regions that have been linked to other cancers, suggesting they share underlying mechanisms that can cause cancer. 

Scientists already knew that women with the BRCA gene faults are at greater risk of breast and ovarian cancers. This new study has established that the 5% of the women who carry the BRCA1 or BRCA2 fault and also have many of the “typos”, have more than an 80% chance of developing breast cancer by the time they’re 80. 

“The next step is to develop ways to bring this information into the clinic so that women with spellings mistakes in BRCA1 or BRCA2 can be given their individual risk rating,” Professor Chenevix-Trench said.