Scientists have pinpointed gene variants tied to the risk of developing cannabis use disorder, in which people build up tolerance to weed and struggle to cut back despite negative impacts on their life and health.
The disorder has formal diagnostic criteria in the manual for mental health disorders. But "roughly, what it means is cannabis use that becomes problematic and involves tolerance or other biological signs of dependence, like withdrawal," Dr. Joel Gelernter, a professor of genetics and neuroscience at Yale University School of Medicine and researcher with the U.S. Department of Veterans Affairs (UDVA), told Live Science.
