HTR3A and HTR3B that increased risk for AUD [56] and predicted the response of alcoholics to the 5-HT3 antagonist ondansetron [57]. Although exploratory at this stage and requiring very large sample sizes for validation, these kinds of studies could result in pharmacogenetic therapeutics [57]. At the present time, the only validated finding for pharmacogenetic underpinnings for response to therapeutics is for a functional polymorphism in the μ opioid receptor gene OPRM1, A118G (Asn40Asp) rs1799971 [58]. There have been mixed results from the numerous studies that have been performed, however a meta-analysis has shown that G allele carriers have lower relapse rates than AA homozygotes [59].
