Supplementary Material for: An Exploratory Study on the CHRNA3-CHRNA5-CHRNB4 Cluster, Smoking, and Parkinson’s Disease
datasetposted on 13.01.2011 by Gao J., Xu H., Weinberg C., Huang X., Park Y., Hollenbeck A., Blair A., Schatzkin A., Burch L., Chen H.
Datasets usually provide raw data for analysis. This raw data often comes in spreadsheet form, but can be any collection of data, on which analysis can be performed.
Background: Smokers have a lower risk of Parkinson’s disease (PD). Recent genome-wide association studies (GWAS) have consistently linked several single nucleotide polymorphisms (SNPs) in the CHRNA3-CHRNA5-CHRNB4 cluster on chromosome 15.q25 to smoking behaviors and nicotine dependence. Investigations into these SNPs may help explain the nature and mechanisms of the smoking-PD relationship. Objective: To examine whether the genetic variations that were consistently associated with smoking or nicotine dependence in recent GWAS also predict the risk of PD. Methods: This is a population-based case-control study of 788 physician-diagnosed PD patients and 911 controls, all non-Hispanic Whites. Seven SNPs were selected based on findings from recent GWAS on smoking and nicotine dependence, all from the nicotinic acetylcholine receptor subunits (CHRN) A3-A5-B4. Odds ratios (ORs) and 95% confidence intervals were derived from logistic regression models under the assumption of logit-additive allelic effects. Results: Four SNPs in linkage disequilibrium from the CHRNA3-CHRNA5-CHRNB4 cluster were associated with smoking duration (OR >1.3, p < 0.05). However, none of the SNPs from this cluster was associated with PD risk in the overall analysis or after stratifying on smoking status. Conclusion: This preliminary analysis does not support a relationship between these smoking-related GWAS SNPs and PD.