Researchers from Denmark found that fathers can pass down obesity heritable information contained in their sperm. The findings offer genetic clues that may explain how children born from overweight fathers tend to become obese themselves.
A man's weight has the ability to affect the kind of "epigenetic information" carried by the sperm. The team analyzed the sperm of 13 lean men and 10 overweight men. They found that epigenetic markers varied in the obese men's sperm, especially the ones responsible for brain function and development.
Furthermore, they looked into the sperm of six overweight men who underwent surgical weight loss treatments to see if such procedures can affect the epigenetic markers in the sperm. An average of 5,000 DNA structural variations were discovered in the sperm cells. These changes occurred before and after the surgery.
"Our research could lead to changing behavior, particularly pre-conception behavior of the father," said University of Copenhagen's associate professor Dr. Romain Barrès, who added that the health implications and recommendations during pregnancy could also be directed towards men.
Several health experts in Britain commended the study for being the first to indicate that the nutrition and environment of fathers can affect their children's future health. The team is gearing up for a follow-up study to analyze human embryos born from the sperm of men with varying body weights.
"In humans, it seems that children of obese men have increased risk of developing obesity themselves as well as of autism spectrum disorder," said Babraham Institute's Head of Epigenetics Programme Professor Wolf Reik.
Andrology professor Allan Pacey from the University of Sheffield noted that the study was able to provide supporting evidence to prove that traits can be passed through the father's sperm without an alteration in the genetic code's basic structure. Pacey stressed that until further studies can be done, aspiring parents should maintain healthy lifestyle habits during conception.
The findings were published in the journal Cell Metabolism on Dec. 3.