In a recent paper in the American Journal of Botany, MSI PI George Weiblen (professor, Plant and Microbial Biology; Science Director and Curator of Plants, Bell Museum) and colleagues have developed a genetic test to determine the levels of THC and CBD in the plant Cannabis sativa. If it contains too much THC, the main compound that causes the sensation of being high, federal regulations require that the farmer destroy the crop. CBD, although it has a similar chemical structure, does not cause the same reaction.
The paper can be read on the journal website: JP Wenger, CJ Dabney III, MA El Sohly, S Chandra, MM Radwan, CG Majumder, GD Weiblem. 2020. Validating a predictive model of cannabinoid inheritance with feral, clinical, and industrial Cannabis sativa. American Journal of Botany 107(10): 1423-1432. doi: 10.1002/ajb2.1550. A Research Brief about the paper can be found on the U of M News website: A Genetic Test Predicts THC Versus CBD in Cannabis Plants.
Professor Weiblen uses MSI for next-generation sequencing analysis of plants, including Cannabis sativa.