In another manuscript in this issue of the journal, genome-wide association analysis results for FEV1/FVC in the Framingham Heart Study (FHS) are reported (Wilk et al). Due to differences in genotyping platforms, the most significantly associated SNPs on chromosome 15 in our study were not genotyped in FHS. Analysis of the genotyped SNPs in the chromosome 15 region in the FHS indicated no significant association with COPD, but association with FEV1 percent predicted was observed with one SNP in LD with rs8034191 (rs11636431 p value 0.007). Evaluation of the imputed data for the most significantly associated SNPs in our populations did not show association with COPD in FHS. Several factors could contribute to the absence of association to the COPD phenotype in FHS: (1) The FHS cohort is a population-based collection, while our studies evaluated populations ascertained specifically for COPD; (2) The FHS cohort was recruited over three decades, while our cohorts represent more recent recruitments (in the last 5–10 years)-smoking habits have changed over time, and it is also possible that COPD clinical characteristics have changed over this period;
