Single nucleotide polymorphisms (SNPs) associated with the current number of cigarettes smoked per day (CPD) (square root transformed) with meta-analytic p<10−5, and candidate SNPs from CHRNA3/CHRNA5 and CYP2A6 loci identified by previous studies
| Chr. | Top SNP | Nearest gene within 50 kb | Effect/non-effect allele | B | p | I2 | Q stat. | N/Nimp | Freq. | Effect direction consistent with previous studies | |
| Top SNPs | 3 | rs1881681 | – | C/A | 0.363 | 1.22×10−6 | 33 | 0.22 | 3/0 | 0.88 | – |
| 8 | rs11984631 | – | T/G | 1.351 | 1.56×10−6 | 37 | 0.21 | 2/0 | 0.99 | – | |
| 2 | rs12615264 | SOCS5 (3′ region) | T/G | 0.644 | 3.46×10−6 | 0 | 0.38 | 3/3 | 0.03 | – | |
| 2 | rs11682595 | SOCS5 (3′ region) | T/G | 0.642 | 3.49×10−6 | 0 | 0.41 | 3/3 | 0.03 | – | |
| 2 | rs11125090 | SOCS5 (3′ region) | A/G | 0.641 | 3.58×10−6 | 0 | 0.42 | 3/2 | 0.03 | – | |
| 20 | rs297755 | – | G/A | 0.291 | 4.86×10−6 | 49 | 0.14 | 3/3 | 0.17 | – | |
| 4 | rs3893377 | BST1 (3′ region) | C/T | 0.289 | 4.90×10−6 | 51 | 0.13 | 3/3 | 0.80 | – | |
| 4 | rs10019008 | BST1 (3′ region) | C/T | 0.288 | 4.99×10−6 | 53 | 0.12 | 3/0 | 0.80 | – | |
| 4 | rs11947310 | BST1 (3′ region) | A/C | 0.289 | 5.21×10−6 | 53 | 0.12 | 3/3 | 0.80 | – | |
| 4 | rs10018756 | BST1 (3′ region) | A/T | 0.275 | 7.71×10−6 | 48 | 0.15 | 3/3 | 0.77 | – | |
| Candidate SNPs | 15 | rs1051730 | CHRNA3 (exon, Tyr215Tyr) | G/A | 0.010 | 0.851 | 32 | 0.23 | 3/0 | 0.59 | No |
| 15 | rs16969968 | CHRNA5 (exon, Asp398Asn) | G/A | 0.009 | 0.863 | 30 | 0.24 | 3/2 | 0.59 | No | |
| 15 | rs8034191 | AGPHD1 (intron) | T/C | 0.006 | 0.914 | 5 | 0.35 | 3/0 | 0.59 | No | |
| 15 | rs684513 | CHRNA5 (intron) | C/G | 0.100 | 0.153 | 0 | 0.78 | 3/3 | 0.80 | Yes | |
| 15 | rs578776 | CHRNA3 (3′ UTR) | G/A | 0.052 | 0.388 | 0 | 0.98 | 3/0 | 0.76 | Yes | |
| 15 | rs588765 | CHRNA5 (intron) | T/C | 0.048 | 0.352 | 23 | 0.27 | 3/3 | 0.40 | No | |
| 19 | rs3733829 | EGLN2 (intron) | G/A | 0.005 | 0.930 | 40 | 0.19 | 3/2 | 0.39 | Yes | |
| 19 | rs7937 | RAB4B (3′ UTR) | T/C | 0.027 | 0.590 | 0 | 0.37 | 3/0 | 0.60 | Yes | |
| 19 | rs1801272 | CYP2A6 (exon, Leu160His) | A/T | 0.362 | 0.063 | 0 | 1.00 | 3/3 | 0.96 | Yes | |
| 19 | rs4105144 | CYP2A6 (5′ region) | C/T | 0.069 | 0.217 | 0 | 0.55 | 3/3 | 0.73 | Yes | |
| 19 | rs7260329 | CYP2B6 (intron) | G/A | 0.005 | 0.922 | 0 | 0.76 | 3/0 | 0.68 | Yes | |
| 19 | rs7251570 | CYP2A6 (3′ region) | G/A | 0.105 | 0.052 | 0 | 0.87 | 3/3 | 0.71 | Yes | |
| 19 | rs12461383 | CYP2A7 (3′ region) | G/C | 0.143 | 0.008 | 0 | 0.62 | 3/3 | 0.60 | Yes |
Analyses were adjusted for sex, age, % of predicted forced expiratory volume in 1 s (FEV1) and principal components for genetic ancestry.
P values < 0.05 are depicted in bold. N/Nimp, number of studies contributing to the meta-analysis/number of studies in which SNP was imputed; I2, heterogeneity index; Q stat., p value for Q statistic; p, p value from the fixed effect meta-analysis; Freq., effect allele frequency in 3441 patients with at least one non-missing phenotype from four cohorts studied; Chr., chromosome; B, regression coefficient; UTR, untranslated region; CHRNA3/CHRNA5, cholinergic receptors, nicotinic, alpha 3/5; CYP2A6, cytochrome P450, family 2, subfamily A, polypeptide 6.