A man’s weight affects the genes he passes on to his offspring

News & Analysis

7th December 2015

Your health could be influenced by the lifestyle of your parents before you were born, according to a study published in the medical journal Cell Metabolism.

The study, led by researchers from the Novo Nordisk Foundation Centre, has found that sperm possess different epigenetic marks in healthy men and obese men.

The researchers followed six men before and one year after gastric bypass surgery to find out how the surgery affected the epigenetic information contained in their sperm cells. An average of 4,000 structural changes to sperm cell DNA were observed a year after the surgery.

Romain Barrès, the study’s lead author, said: ‘We certainly need to further examine the meaning of these differences; yet, this is early evidence that sperm carries information about a man’s weight. And our results imply that weight loss in fathers may influence the eating behaviour of their future children.

‘Epidemiological observations revealed that acute nutritional stress, eg famine, in one generation can increase the risk of developing diabetes in the following generations.’

Epigenetic marks have been shown to control the expression of genes in insects and rodents, but this study identifies the molecular carrier in human gametes that may be responsible for this effect, according to Barrès.

Ida Donkin, one of the study’s lead authors, said: ‘We know that children born to obese fathers are predisposed to developing obesity later in life, regardless of their mother’s weight. It’s another critical piece of information that informs us about the very real need to look at the pre-conception health of fathers. And it’s a message we need to disseminate in society.’

The study’s authors say this research disrupts the current assumption that the only thing our gametes carry is genetic information, and opens up the possibility of new intervention strategies to prevent the transmission of conditions such as obesity to future generations.