The laws of many countries believe that marijuana is used for recreational or medical purposes being different use of industrial hemp. But when it comes down to genetics, marijuana and hemp are not very different at all.

Both marijuana and hemp plants belong to the genus cannabis and both contain enzymes that produce cannabinoids. The difference is only in the last step of the production process of cannabinoids, where cannabigerol (CBG) becomes tetrahydrocannabinol (THC) or cannabidiol (CBD).

The hemp plants produce larger quantities of CBDA synthase enzyme, which converts the CBG to CBDA. Marijuana plants, on the other hand, produce greater amounts of THCA synthase, which converts CBG THCA. CBDA and become THCA CBD and THC when heated.

Since plants hemp and marijuana are very similar in appearance, scientists have been trying to identify a genetic marker that could provide simple screening methods to distinguish the two.

Now a team of scientists in Germany say they have succeeded in achieving just that.

Published this week in the Journal of Forensic Science, researchers showed that by using the polymerase chain reaction (PCR) methods to detect specific phenotypes within synthase gene THC could identify plants cannabis sativa to be rich in CBD or rich in THC.

The accuracy of the test was confirmed by screening a batch of more than 200 plants mixed type.

Unfortunately, the test does not provide a quantitative value of THC content. However, other technologies such as gas chromatography and allows precise analysis of THC content. Scientists believe their test method could be used when analyzing THC is not an option.

Although a quantitative prediction of THC content cannot be done, the marker represents a valuable tool for the evaluation of material cannabis, if an assessment of THC is not possible.

This, they say, could include cases where the plants have not yet reached maturity. For example, in assessing the purity of seed lots.

In addition, researchers say their test could be used in different parts of the plant, including those not normally produce cannabinoids, such as roots or fragments badly damaged plants.