Cannabinoid Receptor Gene Variations in Drug Addiction and Neuropsychiatric Disorders

Cannabinoid receptors (CBRs) are involved in neuropsychiatric disturbances including drug addiction. Studies show that single nucleotide polymorphisms (SNPs) of CNR1 and FAAH may contribute to drug addiction and other neuropsychiatric disorders. However, cannabinoid type-2 receptors (CB2Rs) in the CNS and their role in drug addiction and neuropsychiatric disorders have been much less well characterized. Features of CBR gene structures and their variants in drug abuse and neuropsychiatric disorders and in rodent models were studied. Association studies were performed between polymorphisms in CNR2 gene and neuropsychiatric disorders in two independent case-control populations. We identified novel human and rodent CB2R isoforms with differential tissue expression patterns and regulation by CBR ligands. There is association between polymorphisms of CB2R gene and neuropsychiatric disorders investigated with increased risk of schizophrenia, depression, drug abuse, and eating and autism spectrum disorders in low CB2R function. CBR variants may provide a deeper insight and novel targets for the effects of cannabinoids in drug addiction and other neuropsychiatric disorders.