WASHINGTON, May 16 (UPI) -- The health condition and lifestyle choices of fathers have increasingly been shown to affect newborns and children in ways thought to apply only to mothers.
Researchers at Georgetown University have found paternal influence is much stronger than often thought, finding in a recent review of studies that everything from alcohol consumption to age can play a role in the development of birth defects and gene expression in their children.
Previous studies have shown that health conditions of a father, beyond the basic influence of genetics, can have significant effects on the future health of a child -- including a study last year showing the effect of obesity on sperm changes the way they express genes, making it more likely children will become obese.
"This new field of inherited paternal epigenetics needs to be organized into clinically applicable recommendations and lifestyle alternations," Dr. Janna Kitlinska, an associate professor of biochemistry and molecular and cellular biology, at Georgetown University, said in a press release. "And to really understand the epigenetic influences of a child, we need to study the interplay between maternal and paternal effects, as opposed to considering each in isolation."
For the study, published in the American Journal of Stem Cells, researchers reviewed more than 50 studies with humans and animals focused on links between paternal health and heritable epigenetic programming.
Among their findings, the researchers found advanced age is linked to schizophrenia, autism and birth defects; obesity is linked to enlarged fat cells and changes in metabolic regulation; psychosocial stress is linked to behavioral issues in offspring; and drinking problems were linked to decreased birth weight, reduction in brain size and impaired cognitive function.
The researchers point to gaps in previous studies, such as considering the combination of both parents' environmental and lifestyle conditions. The studies also do not establish that fathers necessarily cause defects and disabilities in offspring -- but there is some link.
In addition to understanding the links, the researchers also write in the study that future research should be conducted with clinical applications of knowledge in mind to intervene for the purpose of prevention.
"We know the nutritional, hormonal and psychological environment provided by the mother permanently alters organ structure, cellular response and gene expression in her offspring," Kitlinska said. "But our study shows the same thing to be true with fathers -- his lifestyle, and how old he is, can be reflected in molecules that control gene function. In this way, a father can affect not only his immediate offspring, but future generations as well."