A research team comprised of researchers from Yale University and the U.S. Department of Veterans Affairs (USVA) conducted a genome study to understand cannabis use disorder and potential links to risks, including lung cancer, mental disorders, and excessive use of tobacco and other substances. The study identified approximately 22 genetic variants linked to cannabis use disorder (CanUD). The findings published in the journal Nature Genetics indicate an association between increased lung cancer risk and genetic variants associated with cannabis use disorder.
The research team examined genetic variants in individuals from multiple ancestry groups enrolled in the U.S. Department of Veterans Affairs Million Veteran Program (MVP is one of the world’s largest genetic databases). The researchers combined this data with expanded samples from iPSYCH2 and an integrated health system called Mass General Brigham (MGB) BioBank and then meta-analyzed these inputs with the Psychiatric Genomics Consortium (PGC). The meta-analysis included 1,054,365 individuals from four broad ancestry groups (European n = 886,025, African n = 123,208, admixed American n = 38,289, and East Asian n = 6,843).
The study showed that variants of genes that encode for three different types of receptors on neurons were associated with an elevated risk of developing cannabis use disorder. The team used population-specific methods to determine single nucleotide polymorphism-based heritability within each ancestry. They observed statistically significant single nucleotide polymorphism-based heritability for CanUD in all populations except for the East Asian (smallest) population. They found genome-wide significant loci unique to each ancestry. There were 22 in the European ancestry group, 2 in African, 2 in the East Asian, and 1 in admixed American ancestry.
The study is currently the most extensive genome-wide study of cannabis use disorder to date in the emerging cannabis research field. It provides a critical base for further studies investigating public health implications. Future studies must also distinguish risks associated with cannabis and tobacco consumption levels.
Sources: Eureka News Alert, Nature Genetics
