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Plainsman1963

New DNA ‘fingerprinting’ technique separates hemp from marijuana
What: DNA fingerprinting to separate hemp from marijuana
When: Published in March Journal of Forensic Science
Who: George Weiblen, assistant professor, plant biology department
03-22-06 | UMN.EDU

MINNEAPOLIS / ST. PAUL (3/22/2006) -- Using new DNA “fingerprinting” techniques, two University of Minnesota researchers have become the first to unequivocally separate hemp plants from marijuana plants with genetic markers. Hemp, a crop grown for durable fiber and nutritious seed, and marijuana, the most abundant illegal drug of abuse in the United States, both belong to the species Cannabis sativa. They differ in levels of the psychoactive drug tetrahydrocannabinol (THC) but are otherwise difficult to tell apart. The technique holds promise for distinguishing different cultivars (domesticated plant lines) in U.S. criminal cases. It may also prove useful in countries where the cultivation of hemp is permitted but marijuana is illegal, as in Canada and Europe. The work appears in the March issue (volume 51, No. 2) of the Journal of Forensic Science.

The new technique is an improvement on previous means of separating the two types of Cannabis, said author George Weiblen, an assistant professor of plant biology in the university’s College of Biological Sciences and College of Food, Agricultural and Natural Resource Sciences. For decades it has been possible to identify THC chemically, but the drug is not present in all plant tissues or throughout a plant’s life cycle. And other researchers have found that genetic markers known as “short tandem repeats,” which are used to identify individuals in paternity and criminal cases, lack the power to distinguish Cannabis cultivars unequivocally.

In tests with three different cultivars of hemp and one of marijuana, the DNA fingerprints of all the cultivars were distinct and nonoverlapping. Weiblen and Shannon L. Datwyler, a postdoctoral associate who is now on the faculty of California State University, Sacramento, found that the AFLP (amplified fragment length polymorphism) technique generated hundreds of genetic markers that together established separate identities for each of the four cultivars.

“We think this technique has the potential to distinguish marijuana varieties as well,” said Weiblen. “It has implications not just for separating hemp from marijuana in countries where hemp cultivation is permitted, but in establishing origins of seized drugs and, therefore, conspiracy in drug distribution networks. It also could be used in criminal defenses against claims of conspiracy.”

The technique chops up DNA and generates numerous fragments of DNA, each defined by particular “marker” DNA sequences that act like bookends. The lengths of the fragments within the bookends were found to vary according to the cultivar. Thus, the pattern of fragment lengths adds up to a composite picture of each cultivar.

“With this technique, we find hundreds of markers scattered across the genome,” said Weiblen. “The larger number of markers, compared to other techniques, gives us the power to separate the cultivars.”

The Cannabis plant has been cultivated for millennia and is important in the global economy as both a licit and an illicit crop, said Weiblen. Hemp is a source of durable fiber that provides an alternative to cotton fabric, among other uses. Cotton requires pesticide application and a hot climate, whereas hemp does not, which makes it suitable for local Minnesota agriculture. Weiblen seeks to screen a wider range of Cannabis cultivars to refine the technique. He is also working to identify regions of the Cannabis genome responsible for drug content in marijuana. If enough can be learned about the genome, it may one day be possible to produce an entirely drug-free hemp plant that looks different from marijuana. Currently, all hemp products are imported into the United States. Developing a new variety that could be cultivated in the United States would reduce American dependence on foreign products while creating a new alternative crop for American farmers.

The work was funded by the University of Minnesota and the David and Lucille Packard Foundation.

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Arise -SWS-

Hey! Instead of wasting time creating a genetically modified hemp plant, just let people grow hemp. A five year old child can be taught how to separate hemp from marijuana. HEMP = TALL, STALKY, LEAFY, TINY SEEDY BUDS. MARIJUANA = SHORT, STOCKY, BIG FAT STICKY STINKY SEEDLESS BUDS.

I'm only 22 and I'm so sick of all the bullshit I see when it comes to the way things work in this world. You don't need DNA fingerprinting to separate hemp from marijuana, just look at the plant, you over-zealous tits. What I see here is a bunch of scientists and DEA officials circle jerking in a conference room.

MrIMStoned

Both can have seeded or non-seeded buds. Other than that I agree that its a waste of time. Alot of countries already grow hemp and there isn't anything negative coming of it.

__________________
"In the end the Party would announce that two and two made five, and you would have to believe it. It was inevitable that they should make that claim sooner or later: the logic of their position demanded it. Not merely the validity of experience, but the very existence of external reality, was tacitly denied by their philosophy. The heresy of heresies was common sense. And what was terrifying was not that they would kill you for thinking otherwise, but that they might be right. For, after all, how do we know that two and two make four? Or that the force of gravity works? Or that the past is unchangeable? If both the past and the external world exist only in the mind, and if the mind itself is controllable what then?"

Plainsman1963

That isn't what they are doing. They are just identifying the differences between the plant using genetic markers. Not modifying anything.
A little simplistic there. Cannabis (as opposed to hemp) grown outdoors can reach the same heights as hemp.
In fact, if you are growing hemp for seed, it can be hard to distinguish between the two.
Now if you are growing for the stalk, well they are planted so close together that trying to sneak a cannabis plant in there would be counterproductive.

And in most of the country there is enough feral hemp growing, that you will not get sensimilla. There will be seeds.

Being able to differentiate between hemp and high thc cannabis would be very useful in the legalization battle for hemp.

However, in the war on drugs, this could be a bad moon rising for cannabis users.

Tolerance4all

"He is also working to identify regions of the Cannabis genome responsible for drug content in marijuana. If enough can be learned about the genome, it may one day be possible to produce an entirely drug-free hemp plant that looks different from marijuana."

Sure sounds like GM to me.

 

chronic2

And why do we want to legalize hemp? Nylon rope works fine for me.

Plainsman1963

Ok, so one day they may be modifying...Right now they are identifying...I stand corrected...Sort of.

As to why legalize hemp?
Because of the potential for bio-fuel.
Because of the multi-million dollars being spent on hemp products that we currently have to import because it's illegal to grow it ourselves.
Because of the agricultural benefits (reduce pesticides, etc.) that hemp provides.

And many many more reasons...