Ancient viruses are probably why Weed has THC and CBD

Humans have been using cannabis for millennia, but scientists still have little knowledge of devil's lettuce. Thanks to new research, we now have a potential answer to a persistent mystery of the science of pots: why does the weed have special chemical compounds that affect humans and other non-plants?

I am talking, of course, about THC and CBD, compounds known as cannabinoids, which are found in cannabis and have various effects on humans. THC is well known as the main psychoactive component of cannabis (that is, it makes you go up), and CBD has recently become a fashionable ingredient as an ingredient in everything from beverages to to cosmetics.

According to a study published in the November 1945 issue of Genome Research these two distinct compounds did not always exist in the plant that we now call cannabis. According to this study, millions of years ago, old viruses could have colonized the genome of the plant and accelerated an evolutionary process modifying its DNA and generating THC and CBD.

"Proteins [for THC and CBD] are embedded in this huge mess of virus-like sequences," said Tim Hughes, professor of molecular genetics at the University of Toronto and co-author of the study , by telephone. "Something that is known for these sequences makes it easier to rearrange the chromosome, and they are actually a bit dangerous in that way."

According to Hughes, these viruses may have accelerated an evolutionary process resulting in a single event. enzymatic gene of cannabis mutated in two, to finally give us the THC and the CBD. "It's easy to imagine that over a long period of time this process has been repeated many times in this part of the chromosome where these two enzymes are found," he said.

This change led to a split of ancient cannabis into chemically distinct types. and humans were then selected for plants with the desired characteristics, such as a high THC, according to a press release published for the study.

It's hard to say what cannabis was before the ancient viruses help him develop the properties we're familiar with, but according to Hughes, some of his closest relatives are harmless plants such as the mulberry and hops.

Read More: Canadian researchers are delighted to have access to a legal weed

The discovery that ancient viruses are probably the reason people turn on cannabis for relax is a by-product of Hughes and colleagues' research, which is the first complete map of the cannabis genome to be published academically. In February, Colorado-based start-up, Sunrise Genetics, unveiled a cannabis genome map at a conference but did not publish an article, claiming that it would share work publicly "in less than a year". Hughes and his colleagues have published a cannabis project. genome in 2011, but it was not detailed enough to reveal the position of genes on the chromosome.

Such maps are essential for improving our impoverished understanding of the cannabis plant. Hughes and his colleagues already do more than discover the possible role of viruses in the production of THC and CBD. According to the researchers, they also identified a gene responsible for the production of a third cannabinoid called CBC.

Much remains to be learned about a plant that many people consume regularly, but science has not yet fully understood. According to Hughes, one of the most important is the use that THC and CBD have for the cannabis plant itself, baduming that these compounds developed well before humans roamed the Earth. "It's just fortuitous that they have these effects on people," Hughes said.

We could soon see more studies deepening the fundamental unknowns of cannabis science with a new wave of research following the legalization of the plant in Canada. Previously, it was difficult for researchers to get their hands on the plant to study and the money needed to conduct their research. Now this is changing and our understanding of cannabis too.

"It's a plant and it does these biochemical things, and it's not like we do not have the ability to do everything we can with other plants, animals, and microbes," said Hughes. "It's just that no one did it because we could not."

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