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 .
Nicotinic acetylcholine receptor β2 subunit gene implicated in a systems-based candidate gene study of smoking cessation
Although the efficacy of pharmacotherapy for tobacco dependence has been previously demonstrated , there is substantial variability among individuals in treatment response . We performed a systems-based c and i date gene study of 1295 single nucleotide polymorphisms ( SNPs ) in 58 genes within the neuronal nicotinic receptor and dopamine systems to investigate their role in smoking cessation in a  bupropion placebo-controlled  r and omized clinical trial . Putative functional variants were supplemented with tagSNPs within each gene . We used global tests of main effects and treatment interactions , adjusting the P-values for multiple correlated tests . An SNP ( rs2072661 ) in the 3′ UTR region of the β2 nicotinic acetylcholine receptor subunit ( CHRNB2 ) has an impact on abstinence rates at the end of treatment ( adjusted P = 0.01 ) and after a 6-month follow-up period ( adjusted P = 0.0002 ) . This latter P-value is also significant with adjustment for the number of genes tested . Independent of treatment at 6-month follow-up , individuals carrying the minor allele have substantially decreased the odds of quitting ( OR = 0.31 ; 95 % CI 0.18–0.55 ) . Effect of estimates indicate that the treatment is more effective for individuals with the wild-type ( OR = 2.14 , 95 % CI 1.20–3.81 ) compared with individuals carrying the minor allele ( OR = 0.83 , 95 % CI 0.32–2.19 ) , although this difference is only suggestive ( P = 0.10 ) . Furthermore , this SNP demonstrated a role in the time to relapse ( P = 0.0002 ) and an impact on withdrawal symptoms at target quit date ( TQD ) ( P = 0.0009 ) . Overall , while our results indicate strong evidence for CHRNB2 in ability to quit smoking , these results require replication in an independent sample
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 .