Obese fathers may raise their daughters' breast cancer risk, say researchers.
Lead investigator Sonia de Assis, Ph.D., of the Department of Oncology at Georgetown Lombardi Comprehensive Cancer Center in Washington, D.C., and colleagues present their findings in the journal Scientific Reports.
To address this research gap, the researchers conducted a study in which they fed male mice either a normal diet (the controls) or an obesity-inducing diet, before mating them with normal-weight female mice.
The researchers then analyzed the breast tissue and rates of breast cancer among offspring.
Compared with female pups with normal-weight fathers, those with obese fathers were overweight at birth, had delayed breast tissue development, and were more likely to develop breast cancer.
On analyzing the sperm of the obese fathers, the team found it had an altered microRNA (miRNA) signature - molecular strands that regulate gene expression. The same altered miRNA expression was found in the breast tissue of their female offspring.
Increased birth weight was also identified among male offspring of obese fathers, but the team says the finding was not statistically significant.
Overall, the authors say their findings indicate that miRNAs pass on epigenetic information from obese fathers to their daughters.
The researchers say they now plan to investigate whether their findings apply to humans.
