As more states legalize marijuana use, an international team of researchers led by scientists at Washington University School of Medicine in St. Louis has identified two regions in our DNA — one newly identified and a second that replicates a past finding — that appear to contribute to one’s risk of becoming dependent on marijuana.
Researchers analyzed DNA and other data from almost 21,000 people diagnosed with cannabis use disorder and another 360,000 who did not have that diagnosis. They found an association with cannabis use disorder in a region of DNA near the FOXP2 gene on chromosome 7, a gene previously linked to language development and to risk-taking behavior. They also implicated a region on chromosome 8. The CHRNA2 gene in that region had been linked to cannabis use disorder in prior studies. It also has been linked to nicotine addiction.
The researchers also identified behavioral factors linked to problems with marijuana via their genetic overlap, such as risk-taking behavior, schizophrenia and lower levels of educational attainment.