Many may already know that using marijuana can lower a man’s sperm count, but it may also cause genetic changes to the sperm as well.
A new study published in the journal Epigenetics has found that the drug could cause these genetic changes to the sperm which may lead to trouble for couples trying to conceive.
Scientists at Duke University compared the sperm of two groups of rats. One group had been given tetrahydrocannabinol (THC), the psychoactive ingredient in cannabis, and the other group did not.
The researchers then compared the sperm of 24 human men who smoked marijuana weekly versus a control group who used marijuana no more than 10 times in their life and not at all in the past half-year. In both cases — rats and humans — marijuana changed how genes work in sperm cells.
Susan Kay Murphy, a professor of gynecology at Duke and co-author of the study says, “Think of your DNA as a list of instructions for making proteins, and genes as small subsets of that list. Our body has little chemical tags (called methyl groups) that get added to the DNA at specific regions.”
She adds, “These chemicals don’t mutate the genes themselves, but they do affect how they’re used, like deciding which instructions are followed and which aren’t.”
“This is a smaller study, but with concerning implications,” says Bobby Najari, a urologist at NYU Langone who had no part in the study.
“I want to be very careful to not have the results turned into something that they’re not,” assures Murphy. “It’s not intended to scare people. Our whole objective is to learn more about biology and what effects there might be.”