Results : We confirmed the importance of the 4 main factors influencing SC : ( 1 ) environmental factors , ( 2 ) genomic factors , ( 3 ) gene-environment interactions , and ( 4 ) evidence -based interventions .
The model demonstrates the complex network of factors influencing SC .
Background : Smoking behaviour is a major public health problem worldwide .
Several sources have confirmed the implication of genomic factors in smoking behaviour .
These factors interact both with environmental factors and interventions to develop a certain behaviour .
Objectives : Describing the environmental and genomic factors as well as the interventions influencing smoking cessation  ( SC ) and developing a working model incorporating the different factors influencing SC were our main objectives .
Catechol-O-Methyltransferase (COMT) Gene Variants Predict Response to Bupropion Therapy for Tobacco Dependence
BACKGROUND Although bupropion is efficacious for smoking cessation , only a minority of smokers are able to quit . Pharmacogenetic research may improve treatment outcomes through discovery of DNA sequences predictive of successful pharmacotherapy for subgroups of smokers . We investigated variants in the catechol-O-methyltransferase ( COMT ) gene in a smoking cessation trial of bupropion . METHODS A double-blind , placebo-controlled , 10-week trial of bupropion and counseling ( with a 6-month follow-up period ) was conducted at two university-based smoking cessation research programs . Abstinence was biochemically verified at the end of treatment and at 6 months after the target quit date . RESULTS At the end of the treatment phase , statistically significant interaction effects indicated that COMT haplotypes of two SNPs ( rs737865 and rs165599 ) predicted the efficacy of bupropion compared with placebo . This interaction effect was attenuated at 6-month follow-up . CONCLUSIONS COMT haplotypes at rs737865 and rs165599 may predict a favorable outcome for bupropion treatment for smoking cessation . European-American smokers with a G allele at both SNPs may not benefit from bupropion treatment . Small numbers of some COMT haplotypes limit interpretation of response . If study findings are confirmed in additional large studies , COMT genotyping could be applied to identify likely responders to bupropion treatment for smoking cessation
Results : We confirmed the importance of the 4 main factors influencing SC : ( 1 ) environmental factors , ( 2 ) genomic factors , ( 3 ) gene-environment interactions , and ( 4 ) evidence -based interventions .
The model demonstrates the complex network of factors influencing SC .
Background : Smoking behaviour is a major public health problem worldwide .
Several sources have confirmed the implication of genomic factors in smoking behaviour .
These factors interact both with environmental factors and interventions to develop a certain behaviour .
Objectives : Describing the environmental and genomic factors as well as the interventions influencing smoking cessation  ( SC ) and developing a working model incorporating the different factors influencing SC were our main objectives .