Polymorphisms of the DRD2 , ANKK1 , DAT1 , DBH , and DRD4 genes have been found to moderate the effects of pharmacotherapy  of alcohol , opioid , and cocaine use disorders .
The integration of genetic information with clinical data will inform health professionals of the most efficacious pharmacotherapeutic intervention for substance use disorders .
Substance use disorders have significant personal , familial , and societal consequences .
Despite the serious consequences of substance use , only a few therapies are effective in treating substance use disorders , thus highlighting a need for improved treatment practice s. Substance use treatment response depends on multiple factors such as genetic , biological , and social factors .
It is essential that each component is represented in treatment plans .
The dopaminergic system plays a critical role in the pharmacotherapy for addictions , and an underst and ing of the role of variation of genes involved in this system is essential for its success .
Naltrexone modification of drinking effects in a subacute treatment and bar-lab paradigm: influence of OPRM1 and dopamine transporter (SLC6A3) genes.
BACKGROUND Naltrexone is moderately effective for the treatment of alcohol dependence , but there is great individual variability . The opioid receptor ( OPRM1 ) single nucleotide polymorphism ( SNP ) asn40asp has been shown to alter alcohol and naltrexone response in animals and humans . In addition , the brain opioid and dopamine systems interact and might underlie drinking and craving . This study investigated the effects of the OPRM1 SNP and dopamine transporter ( DAT ) variable number of t and em repeat ( VNTR ) genetic differences on drinking , alcohol effects , and naltrexone response under controlled conditions in nontreatment-seeking alcoholics . METHODS Two hundred and sixty-five nontreatment-seeking individuals with alcohol dependence were genotyped a priori for the OPRM1 asn40asp SNP and post hoc for DAT ( SLC6A3 ) 9 and 10 VNTRs . Asp40 carriers ( n = 43 ) and matched asn40 homozygotes ( n = 40 ) were r and omized to naltrexone or placebo for 7 days before receiving a priming drink and limited-access alcohol consumption in a bar-lab setting . Effects of genotypes on natural drinking as well as drinking , alcohol effects , and response to naltrexone in the bar-lab setting were examined by genotype . RESULTS There were no significant main effects of naltrexone or OPRM1 genotype , or any medication by OPRM1 interaction , on drinking variables . However , in individuals who had at least one DAT 9 VNTR , and who were also OPRM1 asn40 homozygotes , naltrexone reduced drinks/d consumed under natural conditions ( p = 0.006 ) , but not in the bar-lab . OPRM1 asn40 homozygotes ( p = 0.028 ) and DAT 9 VNTR carriers ( p = 0.032 ) had more stimulation to alcohol after the priming drink . CONCLUSIONS This study does not support a salient role for the OPRM1 asp40 alone in predicting drinking or naltrexone effects . However , although exploratory and in need of replication , it introduces the possibility that epistasis between the OPRM1 gene and DAT gene might need to be taken into account when examining differential genetic response to alcohol or medication treatment , especially in early-stage alcoholics
Polymorphisms of the DRD2 , ANKK1 , DAT1 , DBH , and DRD4 genes have been found to moderate the effects of pharmacotherapy  of alcohol , opioid , and cocaine use disorders .
The integration of genetic information with clinical data will inform health professionals of the most efficacious pharmacotherapeutic intervention for substance use disorders .
Substance use disorders have significant personal , familial , and societal consequences .
Despite the serious consequences of substance use , only a few therapies are effective in treating substance use disorders , thus highlighting a need for improved treatment practice s. Substance use treatment response depends on multiple factors such as genetic , biological , and social factors .
It is essential that each component is represented in treatment plans .
The dopaminergic system plays a critical role in the pharmacotherapy for addictions , and an underst and ing of the role of variation of genes involved in this system is essential for its success .