By analyzing the genomes of more than one million people, researchers have identified stretches of DNA that may be linked to cannabis addiction. They also found that some of the same regions of the genome are associated with other health conditions, such as lung cancer and schizophrenia.
The findings are evidence that cannabis addiction "may have significant public health risks if its use increases," said Daniel Levy, a medical neuroscientist at Yale University in New Haven, Connecticut, and co-author of the study.
Recreational use of cannabis is legal in at least 8 states, and 48 states have legalized the drug's medical use for conditions including chronic pain, cancer and epilepsy. But a third of people who take cannabis end up becoming addicted or using the drug in a way that damages their health. Previous studies have suggested there is a genetic component, and have shown links between problematic cannabis use and certain cancers and mental disorders.
Drug taking and addiction can be influenced by both genes and the environment, making them extremely difficult to study, Levy says. However, the team was able to build on the data from previous work by incorporating genetic information from additional sources, primarily from the Million Veterans Program, a US-based biobank with a large genetic database that aims to improve health care for veterans. The analysis spanned multiple ethnic groups, the first time a genetic study has looked at cannabis abuse.
In addition to identifying areas of the genome that could be affected, the researchers found a bidirectional link between excessive cannabis use and schizophrenia, meaning the two conditions may influence each other. This finding is intriguing, says Marta Di Forti, a psychiatrist and scientist at King's College London. Cannabis use "is the most preventable risk factor" for schizophrenia, she says, adding that the kind of genetic data examined in the study could be used in the future to identify and help people at increased risk of developing mental disorders due to use. of cannabis. /BGNES
