By sequencing genetic samples of the plant, they found that the species had most likely been domesticated during the early Neolithic period. They said their conclusion was supported by pottery and other archaeological evidence from the same period found in present-day China, Japan and Taiwan.
But Prof Purugganan said he was skeptical of conclusions that the plant was developed for drug or fiber use 12,000 years ago, as archaeological evidence shows constant use or presence of cannabis for these purposes began about 7,500 years ago.
“I would like to see a much larger study with a larger sample,” he said.
Luca Fumagalli, study author and biologist in Switzerland specializing in conservation genetics, said the theory of a Central Asian origin was largely based on observational data from wild samples in that region.
“It’s easy to find wild samples, but they’re not wild types,” Dr Fumagalli said. “These are plants that have escaped captivity and have readapted to the wild environment. “
“By the way, that’s why you call it weed, because it grows anywhere,” he added.
The study was led by Ren Guangpeng, a botanist at Lanzhou University in Gansu Province, western China. Dr Ren said in an interview that the origin site of the domestication of cannabis was most likely northwestern China, and this finding could aid current efforts in the country to breed new types of hemp.
To conduct the study, Dr. Ren and his colleagues collected 82 samples, seeds or leaves, from around the world. The samples included strains bred for fiber production and others from Europe and North America that were bred to produce large amounts of tetrahydrocannabinol (THC), the most mood-altering compound in the world. plant.
Dr Fumagalli and his colleagues then extracted genomic DNA from the samples and sequenced them in a laboratory in Switzerland. They also downloaded and reanalyzed sequencing data from 28 other samples. The results showed that the wild varieties they analyzed were in fact “historical escapes of domesticated forms” and that the existing strains in China – cultivated and wild – were their closest descendants from the ancestral gene pool.