Tim Hughes, professor of cellular and biomolecular research at U of T, co-led the research project. He explains that they were comparing the plants cultivated as hemp, which is often grown for food or to produce textiles, and marijuana, which is smoked for its medicinal properties or to listen to Frank Zappa.
“We wanted to get the sequence of the genome of Cannabis sativa which is both hemp and marijuana, and at the same time we wanted to understand the differences,” Hughes said at the Terrence Donnelly Centre for Cellular and Biomolecular Research.
The researchers found that hemp lacks a certain enzyme that marijuana has, and therefore does not produce THC, the psychoactive ingredient in marijuana. “That’s why if you smoke hemp you don’t get high as it doesn’t have the enzyme that is required to make THC,” Hughes explained.
This discovery could lead to advantages for current hemp growers. Currently you need a licence through Health Canada to grow hemp because it contains a small amount of THC, which immediately evokes comparisons to its psychedelic counterpart. Professor Hughes thinks it should be possible to get rid of the THC altogether.
“[What] you can do is targeted breeding ... breed and measure DNA sequences... then you can screen for the variants of hemp that don’t make THC,” Hughes said. “People can now genotype their strains and we can assume it will be possible to breed them in a certain way.” These alterations would allow hemp to be grown legally in Canada.
These potential changes to the way hemp is produced could impact Toronto hemp culture. Stores in Toronto sell merchandise such as herbal products, books, fabric, food, and clothing. As it is often a misunderstood plant and culture, the potential alterations in breeding may change the way people view these practices.
However, this research may not be good news for some. Given the recent availability of the sequenced genome, it is possible to apply the same sort of forensics that is used with human DNA. The results that Professor Hughes and his team came to could enable the law enforcement to use DNA to trace the origins of the plant material.
“[Law enforcement agencies] could make a database and genotype the marijuana and probably figure out where people got it from. I don’t know how well that would work, but with the same principals it is possible,” Hughes remarked.
This sequencing of the Cannabis sativa genome by Professor Hughes and his team will open up more information into the biology of the cannabis plant. While the findings may be a buzz kill for some recreational users, the various functions of the plant, such as the making of fabric and food could be further enhanced, in addition to changes in the plant’s regulation. “We have another plant genome sequenced and we can all look at it and analyse it,” said Professor Hughes.