Prenatal care is centered on pregnant women, and concerns are usually focused on the mother's behavior during pregnancy, especially when it comes to habits like smoking or drinking alcohol. But a new study has suggested that fathers are not off the hook, and that research attention should also be paid to how a father's behavior prior to conceiving a child affects fetal development. Reporting in The FASEB Journal, an analysis using a mouse model indicated that alcohol use by fathers exerts an epigenetic influence, although the exact implications are still unclear.
Previous research by other groups has indicated that children can inherit epigenetic factors from their fathers. Epigenetics refers to modifications to the genome, such as chemical tags or structural factors that can impact gene expression but don't change the sequence of the genome. There is still a lot more to learn about the mechanisms underlying this process.
A simple analysis of human history shows that children inherit more from their dads than just DNA, said senior study author Dr. Michael Golding, an associate professor at the Texas A&M College of Veterinary Medicine & Biomedical Sciences (CVMBS). Male behavior should be analyzed too, he said.
“Say you had a parent who was exposed to starvation. They could pass on what you might call a thriftiness, where their kids can derive more nutrition from less food,” said Golding. “That could be a positive if they grow up in a similar environment, or they could grow up in a time when starvation isn’t an issue and they might be more prone to obesity or metabolic syndromes. That kind of data is clearly present in clinical data from humans.”
With a mouse model, this work indicated that offspring of alcohol-exposed fathers have more trouble in the placenta, such as higher rates of fetal growth restriction, a decrease in placental efficiency, and an increase in placental size, said lead study author and graduate student Kara Thomas.
“The placenta supplies nutrients to the growing fetus, so fetal growth restriction can be attributed to a less efficient placenta. This is why placental efficiency is such an important metric; it tells us how many grams of fetus are produced per gram of placenta,” Thomas said. “With paternal alcohol exposure, placentas become overgrown as they try to compensate for their inefficiency in delivering nutrients to the fetus.”
The situation is complex, however. Although those patterns were observed often in male offspring, they varied according to the mother. In female offspring, these patterns were not as common. Golding suggested that the mothers' genetics and the sex of the offspring are also affecting the situation.
More research will be needed to reveal exactly how alcohol consumption by fathers prior to the conception of offspring affects the development of a fetus, but this research has shown that it's a question that should be pursued.
Golding is hopeful that clinicians, as well as society will start to inquire about male prenatal behavior. This issue may become increasingly important as some women have faced criminal charges and jail sentences after the loss of their pregnancies, both in the United States and elsewhere.
“The thing that I want to ultimately change is this stigma surrounding the development of birth defects,” Golding said. “There’s information coming through in sperm that is going to impact the offspring but is not tied to the genetic code; it’s in your epigenetic code, and this is highly susceptible to environmental exposures, so the birth defects that we see might not be the mother’s fault; they might be the father’s or both, equally.”
Sources: Texas A&M University, The FASEB Journal
