Human CHRNB4 blocking peptide

Introduction. Epidemiological studies have described a high comorbidity of substance use disorders with another psychiatric disorder, which has been called dual pathology. However, the aetiological mechanisms underlying this association are still not fully understood. Aim. To carry out a preliminary study of the effect of polymorphism rs1051730 of the gene group CHRNA5-CHRNA3-CHRNB4 through a case-control study. Subjects and methods. A total of 225 subjects were selected and divided into three groups: those diagnosed with bipolar disorder, those with nicotine dependence, and subjects without nicotine dependence or any other psychiatric disorder. Genotyping was performed by real-time polymerase chain reaction. Genetic association analysis was performed using chi-square tests and multivariate logistic regressions. Results. On comparing allelic frequencies with the control group, we found that polymorphism rs1051730 was associated with nicotine dependence (p = 0.03), but not with bipolar disorder (p = 0.94). Conclusion. Variant rs1051730 was associated with nicotine dependence in the Mexican population and showed the same effect in dual pathology. However, further studies are recommended to obtain conclusive results.

Background Two single-nucleotide polymorphisms, rs1051730 and rs16969968, located within the nicotinic acetylcholine receptor gene cluster on chromosome 15q25 locus, are associated with heaviness of smoking, risk for lung cancer, and other smoking-related health outcomes. Previous studies have typically relied on self-reported smoking behavior, which may not fully capture interindividual variation in tobacco exposure. Methods We investigated the association of rs1051730 and rs16969968 genotype (referred to as rs1051730-rs16969968, because these are in perfect linkage disequilibrium and interchangeable) with both self-reported daily cigarette consumption and biochemically measured plasma or serum cotinine levels among cigarette smokers. Summary estimates and descriptive statistical data for 12 364 subjects were obtained from six independent studies, and 2932 smokers were included in the analyses. Linear regression was used to calculate the per-allele association of rs1051730-rs16969968 genotype with cigarette consumption and cotinine levels in current smokers for each study. Meta-analysis of per-allele associations was conducted using a random effects method. The likely resulting association between genotype and lung cancer risk was assessed using published data on the association between cotinine levels and lung cancer risk. All statistical tests were two-sided. Results Pooled per-allele associations showed that current smokers with one or two copies of the rs1051730-rs16969968 risk allele had increased self-reported cigarette consumption (mean increase in unadjusted number of cigarettes per day per allele = 1.0 cigarette, 95% confidence interval [CI] = 0.57 to 1.43 cigarettes, P = 5.22 x 10(-6)) and cotinine levels (mean increase in unadjusted cotinine levels per allele = 138.72 nmol/L, 95% CI = 97.91 to 179.53 nmol/L, P = 2.71 x 10(-11)). The increase in cotinine levels indicated an increased risk of lung cancer with each additional copy of the rs1051730-rs16969968 risk allele (per-allele odds ratio = 1.31, 95% CI = 1.21 to 1.42). Conclusions Our data show a stronger association of rs1051730-rs16969968 genotype with objective measures of tobacco exposure compared with self-reported cigarette consumption. The association of these variants with lung cancer risk is likely to be mediated largely, if not wholly, via tobacco exposure.