Exposure to cannabis by men in their child-bearing years alters the genetic profile of their sperm, says a study conducted at Duke University Medical Center, US.
The study also found that many outside factors can affect sperm, ranging from tobacco smoke to pesticides, flame retardants to obesity, all of which can have epigenetic effects.
Epigenetics are inheritable traits that don’t affect DNA sequencing but typically stem from life experiences.
The new research shows that tetrahydrocannabinol (THC) can affect epigenetics, causing structural and regulatory changes in the DNA of users’ sperm.
The study which examined 24 men discovered that THC appears to target genes in two major cellular pathways and alters DNA methylation, a process essential to normal development
Scott Kollins, senior author of the study, said: “What we have found is that the effects of cannabis use on males and their reproductive health are not completely null.
“In that, there’s something about cannabis use that affects the genetic profile in sperm.”
Susan Murphy, co-author of the study, advised men to steer clear of cannabis when trying to conceive.
She said: “We know that there are effects of cannabis use on the regulatory mechanisms in sperm DNA, but we don’t know whether they can be transmitted to the next generation.”
“In the absence of a larger, definitive study, the best advice would be to assume these changes are going to be there. We don’t know whether they are going to be permanent.
“I would say, as a precaution, stop using cannabis for at least six months before trying to conceive.”