In a population-based case-control multicenter study designed for tobacco addiction research, a total of 551 current smokers of European ancestry and 548 age-matched healthy volunteers (never-smokers) were genotyped for SNP rs4680 and extensively characterized concerning their smoking behavior.
Our COMT Val158Met results suggest that there may be both sex differences in the genetic origins of alcoholism and smoking in this population and overlap in genetic vulnerability to both addictions in women.
Functional alleles that alter alcoholism-related intermediate phenotypes include common alcohol dehydrogenase 1B and aldehyde dehydrogenase 2 variants that cause the aversive flushing reaction; catechol-O-methyltransferase (COMT) Val158Met leading to differences in three aspects of neurobiology: executive cognitive function, stress/anxiety response, and opioid function; opioid receptor micro1 (OPRM1) Asn40Asp, which may serve as a gatekeeper molecule in the action of naltrexone, a drug used in alcoholism treatment; and HTTLPR, which alters serotonin transporter function and appears to affect stress response and anxiety/dysphoria, which are factors relevant to initial vulnerability, the process of addiction, and relapse.