Behavioral inhibition system (BIS) and gene-environment factors associated with African-American smoking behaviors

Purpose: Socio-economic status (SES) is highly correlated with cancer rates and people of lower SES are more likely to engage in behaviors that increase cancer risk, such as tobacco use. Genetic predisposition to Nicotine Dependence (ND) has been linked to the dopamine receptor D2 (DRD2) gene and the Taq1 A single nucleotide polymorphism (SNP) minor allele of the dopamine receptor, specifically rs1800497, which is more prevalent in African-Americans (AA). Although dopamine has been linked to the Behavioral Activation System (BAS) and is involved in multiple addictive disorders, study findings indicate higher Behavioral Inhibition System (BIS) scores among heavier smokers. This study examines the contributions to and associations between environmental socio-demographic and exposure variables, the BIS harm avoidance personality trait and rs1800497 on smoking behaviors in African-American smokers. Methods: A cross-sectional sample of 389 AA smokers from Baltimore, Maryland and Washington, D.C. responded to study questionnaires and donated blood samples for genetic analysis. Data from study questionnaires were merged and analyzed to compare and examine differences among current smokers by mean BIS scores, environmental socio-demographic and exposure variables, cigarettes smoked per day, number of smoking cessation attempts and rs1800497 personality alleles. A 1-way ANOVA and Post-Hoc Least Significance Test (LSD) were used to examine the associations between the alleles for rs1800497 and mean BIS scores. Results: An association was noted between the harm avoidance scores and rs1800497 in AA smokers (1-way ANOVA, p-value=0.039). Conclusion: Additional research is needed to understand the genetic and social determinants contributing to increased smoking behavior in AA smokers.