A girl's breast cancer risk may be influenced by her obese father

It's been thought for some time now that a mother's weight and diet during pregnancy has the potential to affect the breast cancer risk of her female offspring. But now new research suggests that obese father's also risk raising their children's chances of breast cancer, due to the way obesity alters the gene expression of sperm.

Experts have long agreed that a woman's breast cancer risk is influenced by changes in genes, and approximately 5-10 percent of these gene changes are inherited.

According to Sonia de Assis, Ph.D., from the Department of Oncology at Georgetown Lombardi Comprehensive Cancer Centre in Washington, D.C., who led the investigative team, said few studies have previously investigated the link between a father's weight and an offspring's breast cancer risk in later life.

Presenting their findings in the journal Scientific Reports, de Assis and her colleagues outlined how they had studied how both normal weight male mice and obese male mice influence the breast tissue off their offspring. They found that female pups sired by obese males had delayed breast tissue development, and were more likely to develop breast cancer as a result.

They revealed that the obese males' sperm had an altered microRNA (miRNA) signature, which was subsequently found in the breast tissue of their female offspring.

The researchers now plan to conduct more studies to see if the same is true in humans.