DNA research uncovers new cannabis strain
Researchers in the ACT appear to have found a previously unidentified type of cannabis plant which they have dubbed 'rasta'.
There are currently thought to be only two types of cannabis, one prized for its rope-making qualities, the other cultivated for its drug properties.
New Scientist reports that Canberra Institute of Technology (CIT) scientists categorised almost 200 cannabis plants according to their DNA.
CIT spokesman Simon Gilmore says he and colleagues at the institute's Centre for Forensic Science appear to have uncovered another sub-species of the plant.
'Rasta' is not dissimilar to the sativa sub-species but New Scientist reports that it contains more THC, certainly more than the indica sub-species that is used for rope-making.
Mr Gilmore says it could be an ancient line they have identified through DNA.
"What we might be uncovering is really an ancient relationship," he said.
"Cannabis has been used a lot by humans in the last few thousand years and while we have a signature that there might have been three different types of cannabis, what could have happened with human cross-breeding [is] that those distinctions could have been lost by now.
"Three different mitochondrial DNA types in the cannabis that's grown these days, it might imply that cannabis had been domesticated on three separate occasions.
"It seems the first use was for food - cannabis seeds are highly nutritious apparently but not all that tasty."
Mr Gilmore says the object of studying 200 plants was to find markers to track the origins of illegal cannabis.