A mother’s diet during pregnancy no doubt weighs heavily on the development of the fetus. New research suggests it could also impact the offspring of the next generation, namely, the mother’s grandchildren.
Gestational development is still a delicate period of time for a growing fetus. While both parents’ DNA has already been passed on to the child, gene expression is still very much malleable. Researchers believe it’s during these critical moments that the expression of certain genes actually changes, predisposing the child either to a healthy metabolic future or an uncertain one.
A team of scientists from the Hospital Sant Joan de Déu in Spain studying lab mice found that when the mice were given 50 percent of their normal caloric intake during the last week of pregnancy, their offspring were at first underweight. But then as the offspring got older, they became obese and diabetic. The domino effect continued: When those mice gave birth, they passed on the predisposition to metabolic abnormalities. What began as a mother’s poor diet ended with her grandchildren predisposed to genetic maladies.
Study leader Dr. Josep Jiménez-Chillarón argues the inheritance occurs because of a single gene, known as LXR. The expression of the gene regulates the metabolism of fat and cholesterol in the livers of male offspring. Jiménez-Chillarón believes it’s also the specific process of DNA methylation, which cells use to control the expression of certain genes, that drives the changes. The same methylation occurs in the sperm of malnourished mice. “This may contribute, in part, to the transmission of diabetes risk from parents to offspring," he said in a statement.
Jiménez-Chillarón and his colleagues are hesitant to suggest a mother’s diet completely forgives her future offspring’s poor health. Despite the robust effects metabolic predispositions may yield, a healthy lifestyle is still within each person’s control. Disease may originate along a bloodline, but it does not define it. Eating healthier and exercising go a long way toward minimizing, or even erasing, the risk for disease.
“Our view is that we inherit some predisposition, but it is our own lifestyle that will determine whether inherited risk will truly translate into disease,” Jiménez-Chillarón explained. “Hence, a healthy lifestyle is the best way to prevent any potentially inherited or newly acquired obesity or diabetes predisposition."
Such a campaign may be difficult. A recent study showed that the American Medical Association’s new classification of obesity as a disease last June actually compels people to eat more, as they believe their affliction is less of a fixable condition and more of a concrete pathology. Obesity is notorious for leading to diseases such as high blood pressure, heart disease, diabetes, and stroke.
When it comes to disease research, the key is in understanding the tenuous balance between autonomy and genetics. While obesity being labeled a “disease” is naturally contentious, due to the fact a person’s diet is entirely within his or her control (irrespective of hormonal compulsions), the latest research upholds diabetes and metabolic disorders as having legitimate beginnings in the bloodline.
Source: Martinez D, Pentinat T, Ribo S, et al. In Utero Undernutrition in Male Mice Programs Liver Lipid Metabolism in the Second-Generation Offspring Involving Altered Lxra DNA Methylation. Cell Metabolism. 2014.