New York, Nov. 2 (PTI): People who overeat might ruin their grandchildren’s health as a person’s diet could influence future generations, according to a study.
Although diet does not change genes, it could have an effect on future generations, said the study by Swedish researchers, published in Nature magazine. Gunnar Kaati and his team at the University of Umes collected health histories of 300 Swedes born between 1890 and 1920. Crop records showed how much they were eating just before puberty. Grandchildren of well-fed people were four times as likely to die from diabetes, they found, while the children of persons who suffered famine were less likely to die from heart disease.
“It’s a big leap” to say that such effects are passed on to future generations, Eugene Albrecht, who studies foetal growth at the University of Maryland in Baltimore, was quoted as saying. “But I have a gut feeling (Kaati is) right.”
“We have to take this seriously,” argues geneticist Marcus Pembrey of the Institute of Child Health, London.
A father’s nutrition could change the activity of genes in sperm, rather than the genetic code itself, he suggests. Chemical stamps on DNA switch genes on and off. Some of these switches are thrown when sperms begin forming in puberty. Bodies might sense the food supply and set up sperm genes to give children the best chance of survival, says Pembrey.
If, for example, the grandfather’s generation has ample food, the sperm would carry a particular set of switches into the offspring. For the next generation, food might be sparse and the father’s sperms would reprogramme their genes to deal with an erratic food supply.
When the father reproduces, such a stamp might decrease the total number of children, but boost each baby’s growth so that they would be more likely to survive lean times. This process could influence subsequent disease rates, speculates Pembrey. Non-genetic factors might affect a child’s health in other ways, says Nature.
A mother’s stress and diet during pregnancy are thought to shape her baby’s risk of developing conditions such as high blood pressure.
This is also thought to occur by altering gene activity.