February 23, 2017
A University of Pennsylvania study uncovered evidence that the sons - but not the daughters - of cocaine-using fathers have a higher risk of developing learning disabilities.
Researchers from Penn's Perelman School of Medicine conducted the study, which was published Tuesday in the journal Molecular Psychiatry. The team was able to conclude that the use of the drug by fathers could impact the cognitive development of their sons despite never directly exposing them to the drug. The most-common deficiency was memory loss.
“These results suggest that the sons of male cocaine addicts may be at risk for learning deficits,” said Dr. R. Christopher Pierce.
To run the study, which was led Dr. Mathieu Wimmer, researchers injected laboratory rats with cocaine for an extended period of time. The offspring of those rats were assessed through a series of tests. The findings revealed that the male rats could not remember the location of items in their surroundings, but the female rats did not display the same struggles. The male rats also showed impaired function in the hippocampus, a brain region critical for learning and spatial navigation in both humans and rodents.
Further analysis unveiled that cocaine use caused chemical modifications to the father's histones, the proteins that DNA surrounds. After conception, the impact can be found in changes to the brain of their sons. Researchers said the alteration leads to decreased production of D-serine, a molecule essential for memory.
“There is substantial interest in the development of D-serine and related compounds, which are well tolerated by humans, as drug therapies,” Pierce said, noting that the study could lay the foundation for finding a treatment to reverse the effects of paternal cocaine use.
