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 .
Lack of association of DRD2 rs1800497 (Taq1A) polymorphism with smoking cessation in a nicotine replacement therapy randomized trial.
INTRODUCTION We previously reported evidence that the T allele of the dopamine type-2 receptor ( DRD2 ) rs1800497 polymorphism is associated with improved response to nicotine replacement therapy ( NRT ) relative to placebo and that this association may only be present in females . However , evidence of the poor replication validity of genetic association studies is growing , particularly among those that report subgroup analyses . We therefore attempted to replicate our previous finding of an association between the DRD2 rs1800497 genotype and response to NRT in a new , larger cohort , with greater statistical power . METHODS Participants were r and omly assigned to one of two levels of smoking cessation behavioral support ( usual care vs. weekly support ) . All participants received 8 weeks of 15-mg NRT transdermal patch . RESULTS The presence of one or more T alleles was associated with a slightly but not significantly lower likelihood of abstinence at 3 and 6 months . We found evidence of a genotype x sex interaction effect . However , stratified analyses indicated a main effect of genotype opposite to the effect reported previously , with females carrying one or more copies of the T allele less likely to be abstinent . DISCUSSION Our results do not support an association between the DRD2 rs1800497 ( Taq1A ) polymorphism and response to NRT , contrary to our previous study
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 .