Women who are conceived when their father is overweight could be at a 30 per cent higher risk of developing breast cancer, new research suggests.
A number of studies have suggested that a mother's diet and weight in pregnancy affects the breast cancer risk of offspring and some studies have indicated that maternal obesity can alter genes that could raise a child's risk for breast cancer. Now, new research suggests the same may ring true for fathers; being obese alters the gene expression of sperm, which may raise the risk of breast cancer for their daughters.
Now, Scientists at Georgetown University in Washington DC found that obese male mice which mated with normal weight females produced female pups that had an increased chance of developing breast cancer than pups from non-obese fathers.
Assistant professor Dr Sonia de Assis said: "This study provides evidence that, in animals, a fathers' body weight at the time of conception affects both their daughters' body weight both at birth and in childhood as well as their risk of breast cancer later in life.
"Of course our study was done in mice, but it recapitulates recent findings in humans which show that obese men have significant epigenetic alterations in their sperm compared to lean men. Our animal study suggests that those epigenetic alterations in sperm may have consequences for next generation cancer risk."
The study, published in Scientific Reports, suggested miRNAs may carry the epigenetic information from obese dads to their daughters.
“Our animal study suggests that those epigenetic alterations in sperm may have consequences for next generation cancer risk.”
The miRNAs identified regulate insulin receptor signalling, which is linked to alterations in body weight, and other molecular pathways that are associated with cancer development such as the hypoxia signaling pathway.
Future research will explore if the same associations regarding breast cancer risk hold for daughters of human fathers who are overweight around the time of conception.
“Until we know about this association in men, we should stick to what we all know is good advice,” she said.
“Women and men should eat a balanced diet, keep a healthy body weight and life-style not only for their own benefit but also to give their offspring the best chances of being healthy.”