The development and maintenance of an alcohol addiction is a complex interaction between genetic and environmental factors. Genetic effects seem to contribute substantially to the risk of developing an addiction, but also to its course and patients’ responses to different treatments. Recent studies identified associations between polymorphisms in the genes of glutamate and μ-opioid receptors and addiction risk. Those receptors are of special interest, because they are targets of therapeutic agents, such as acamprosate and topiramate.

Several studies were conducted, in order to further determine the effects of genetic polymorphisms in glutamate and opioid receptor genes on addictive behavior, neural response to alcohol cues and relapse risk.

Genetic effects were investigated in samples of alcohol-dependent patients using functional imaging techniques, neuropsychological tests and follow-up investigation after standard clinical treatment. Data on clinical parameters, neuronal response to alcohol cues, functional neuronal connectivity and relapse risk were collected and analyzed.

Results demonstrate effects of genetic polymorphisms in glutamate and opioid receptors on neuronal response to alcohol cues in frontal and mesolimbic brain areas, subjective craving and time to first relapse. Current findings will be discussed in the light of existing evidence on the contribution of genetic effects to treatment outcome and patient stratification.

The investigation of genetic risk factors and mechanisms by which they affect addiction related phenotypes seems to be a promising tool to identify molecular treatment targets and predictors for successful treatment strategies.