According to a latest study fathers on a high-fat diet are more likely to produce daughters with a higher diabetes risk. The study was published in the journal Nature and it involved laboratory rats.
Professor Margaret Morris of the School of Medical Sciences at the University of New South Wales was guiding the PhD study by Sheau-Fang Ng which revealed this finding. According to Professor Morris maternal transmission to offspring is studied previously but this is the first study that looks into the contribution from the father. She said, “In the mothers there are clear mechanisms were that might happen through the uterus. What happens while a foetus is developing can have an impact…but the father has really been a bit of an untapped question.”
For the study the team fed rats a controlled high-fat diet, known to cause obesity and diabetes, for about ten weeks before allowing them to mate. Morris said, “When they were mated, they were obese they had increased insulin and they were glucose intolerant: diabetic if you will.” They found that their female offspring demonstrated abnormalities in the genes in the pancreatic cells, which produce insulin. She said, “What we showed was that the female offspring had changes in their pancreas that seems to go along with a phenotype that is glucose intolerant. When we gave them a glucose test, they were less able to manage that glucose.” She explains that the effect could be genetic, but it is more likely biological. “What we seem to have is an environmental effect, so it's a non-genetic effect, because the only thing we've imposed here is obesity and diabetes in the dad. And that has been transmitted to the offspring,” she explained.
Another significant finding was that the female offspring, despite being on a normal diet, developed glucose intolerance at a very young age. “What we noticed was that they were already glucose intolerant at six weeks and they got worse by twelve weeks effectively between the onset of puberty and adolescence…With the increasing obesity epidemic there's early emergence of type 2 diabetes in younger and younger people, teenagers, so this was part of the drive for the study,” she said.
On the cards she said was a larger sample of animals to give better data for statistical analysis, and to look at whether male offspring show the same impaired insulin synthesis. “I think the interesting thing is, this really represents an advance in our understanding of potential paternal influences on the metabolic health of offspring,” she added.
According to Dr Iain Frame, of British charity Diabetes UK if these results were “translated” to humans, it could help improve health outcomes in people at high risk of developing type 2 diabetes. He added, “We will watch this promising area of research closely.”
Some experts have criticized the results too. Stephen O'Rahilly, a clinical biochemist at the University of Cambridge, UK, said, “the difference in glucose tolerance between these animals is pretty slim, and the number of animals in the study was too few to give a robust signal.” Tracy Bale, a researcher in neuroscience at the University of Pennsylvania in Philadelphia also added, “What this study doesn't discern between is pubertal exposure and adult exposure in the father rats, because Morris's team covered the whole window… So in humans, it does not mean that if a man eats a cheeseburger one night, and mates with his spouse the next day, that they will have a child with β-cell dysfunction. That would be remarkable.” O'Rahilly concluded, “This is an interesting and provocative paper, but science eventually comes out in the wash… If it is real, other people will find it.”