Women conceived when fathers were obese have higher breast cancer risk
Women who were conceived when their father was overweight could be at a 30pc higher risk of developing breast cancer, new research suggests.
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.
The researchers found evidence that obesity changes the miRNA signature, or epigenetic regulators of gene expression, in both the father mouse's sperm and the daughter's breast tissue, suggesting that miRNAs may carry epigenetic information from obese fathers to their daughters.
Epigenetic alterations may have consequences for next-generation cancer risk, said Sonia de Assis, assistant professor at Georgetown University.
The miRNAs that the scientists identified regulate insulin receptor signalling, which is linked to alterations in body weight and other features associated with cancer development, such as hypoxia.
Maternal obesity is believed to influence breast cancer in humans. However, up till now, little research has investigated the influence of overweight fathers.
Sonia de Assis, assistant professor in the department of oncology at Georgetown, said: "Of course our study was done in mice, but it confirms recent findings in humans, which show that obese men have significant epigenetic alterations in their sperm, compared to lean men.
"Our animal study suggests those epigenetic alterations in sperm may have consequences for next-generation cancer risk."
Ms De Assis, who led the research for the new study, which is published in 'Scientific Reports', said the next step would be to establish whether the same associations applied to daughters of human fathers who are overweight at 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 lifestyle, not only for their own benefit but also to give their offspring the best chances of being healthy." (© Daily Telegraph, London)