gene, we could neither identify a common significant SNP nor a common allele tagged by SNPs in linkage disequilibrium (r2>0.5 or D’>0.5). Despite this, the pathway analysis was robust enough to highlight the associations of these two genes to smoking quantity. Indeed, the presence of these moderate signals in CHRNA7 and CHRNA9, as well as the ones in cholinergic muscarinic receptors, sustained the significance of the terms GO:0005892, GO:0042166, GO:0004889 and GO:0015464 for the analysis of the least stringent threshold for SNPs (Table 3). In contrast, the absence of these moderate signals resulted in the terms GO:0035095, GO:0035094 and GO:0007274 only being significant for the analysis of the SNPs that satisfied the most stringent threshold (Table S2).
