A study published in the journal Epigenetics has shown that THC can affect the genetic information carried by sperm, according to The Verge.
Researchers at Duke University performed similar experiments on both rats and humans. On rats, they tested the sperm of rats who had been given cannabis and those that had not. In humans, they tested sperm from men who were weekly consumers of cannabis against sperm from men who hadn’t had any cannabis in the last half-year and had only consumed it a maximum of 10 times in their lives.
The study investigated THC‘s epigenetic effects. Epigenetics is the study of information not explicitly in the genome but rather attached to it via chemical compounds called methyl groups. While the genes themselves don’t change, methyl groups cause changes in the genes’ expression.
In both rats and humans, cannabis was shown to change the amount and placement of methyl groups in specific areas of the genome. One difference related to the size of internal organs in offspring and the other related to the body’s response to cancer.
Researchers were very clear that the exact outcomes of those changes are still uncertain. The study was a pilot designed to see if there were any genetic changes in sperm due to cannabis, which was confirmed. It is not known whether or not the changes are reversible or whether they will actually result in concrete changes in offspring.
“I want to be very careful to not have the results turned into something that they’re not. It’s not intended to scare people. Our whole objective is to learn more about biology and what effects there might be.” — Susan Kay Murphy, a co-author of the study
Researchers hope to study the changes further and are already designing new studies at Duke University.