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 .
Dopamine receptor DRD2 genotype and smoking cessation outcome following treatment with bupropion SR
The A1 allele of the dopamine D2 receptor gene ( DRD2 ) is associated with a reduced number of dopamine binding sites in the brain and with the increased likelihood of substance abuse and addictive behavior . In a study of smokers enrolled in an open-label , r and omized effectiveness trial , we investigated whether variants in the DRD2 receptor gene are associated with smoking cessation outcomes following treatment with a combination of bupropion SR and behavioral counseling .  Adherence to treatment and point-prevalent smoking status were assessed at 3 and 12 months , respectively , following a target quit date . Compared to women who carry both A2 alleles , women with at least one A1 allele were more likely to report having stopped taking bupropion due to medication side effects ( odds ratio (OR)=1.91 , 95 % confidence interval (CI)=1.01–3.60 ; P<0.04 ) and at 12 months were somewhat more likely to report smoking ( OR=0.76 , 95 % CI=0.56–1.03 ; P<0.076 ) . Significant associations or trends were not observed in men . In women , individual variability in responsiveness to bupropion-based treatment may be partially due to differences in genetic variants influencing dopamine receptor function
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 .