Genetic variant increases breast cancer risk

For the first time, QUT and Cancer Council research has found a genetic variant in a particular micro RNA (miR-145) that can influence the risk of breast cancer development.

The research examined genetic variations in 24 micro RNAs, which were already known to influence biological pathways connected to cancer.

Researcher Robert Smith from the Genomics Research Centre at QUT’s Institute of Health and Biomedical Innovation said genetic variation in micro RNAs could have wide-ranging effects.

“Micro RNAs control networks of genes and changes to their function can affect many genes at once,” Dr Smith said.

“We examined the genetic variations in our volunteers – women who have been diagnosed with breast cancer and healthy women with no history of breast cancer, recruited in collaboration with Cancer Council Queensland.

“Of the 24 genetic variations examined, six were found to be too rare to analyse and five could not be interpreted using our methods.

“Twelve of the remaining genetic variations showed no connection to the risk of developing breast cancer.

“The final remaining genetic variation showed an association to the risk of developing breast cancer in both our primary and secondary participant groups.

“The genetic variant found to be connected with breast cancer risk is located in the micro RNA ‘miR-145’, and this study is the first to show that genetic variation in this micro RNA can influence a woman’s risk of breast cancer development.

“Reduced activity of miR-145 has previously been seen in several types of aggressive cancer, and it is possible that the genetic variation we examined reduces miR-145 activity.

“Future studies should examine exactly how this genetic variation affects miR-145 activity to better establish the link to breast cancer risk.”

Around 3100 Queenslanders are diagnosed with breast cancer every year, and about 520 people die from the disease.

Cancer Council Queensland spokesperson Katie Clift said women should be mindful of their breast health and screening recommendations.

“It’s important all women discuss their individual risk of breast cancer and steps to prevent breast cancer with a trained professional,” Ms Clift said.

“All women should be breast aware by checking their breasts regularly. It’s critically important that women who notice changes in their breasts see their doctor immediately.

“If breast cancer is found and treated early, there is increased chance of surviving the disease.”

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or more information or interviews, please contact:

Katie Clift, Executive Manager, Media and Spokesperson, Cancer Council Queensland

Ph: (07) 3634 5372 or 0409 001 171