Table 4. Common and low-frequent SERPINA1 SNPs and their association with AAT serum level, univariate and conditional on significantly associated SNPs (N = 5569a), in SAPALDIA.
| SNP | Location | Position | Selectionb | MAF | Univariatec | Conditionald | ||
| Allele Effect | P | Allele Effect | P | |||||
| rs2896268 | 5′UTR | 93935461 | C | 0.495 | 0.006 | 0.10 | 0.013 | 4.1E-05 |
| rs1956707 | 5′UTR | 93933946 | C | 0.038 | 0.016 | 0.10 | 0.029 | 5.0E-04 |
| rs8004738 | exon 1 | 93926667 | D | 0.490 | 0.005 | 0.15 | 0.001 | 0.81 |
| rs1570142 | intron 1 | 93926015 | A,B,C | 0.488 | 0.005 | 0.19 | 0.001 | 0.88 |
| rs3748312 | intron 1 | 93924017 | A,B | 0.153 | 0.035 | 2.4E-12 | 0.002 | 0.70 |
| rs3748316 | intron 1 | 93923617 | A,C | 0.181 | 0.011 | 0.02 | 0.002 | 0.63 |
| rs3748317 | intron 1 | 93923432 | A | 0.158 | 0.020 | 5.5E-05 | 0.004 | 0.36 |
| rs1980617 | intron 1 | 93922287 | A | 0.389 | 0.030 | 5.0E-16 | 0.003 | 0.31 |
| rs1980618 | intron 1 | 93922176 | A,C | 0.383 | 0.030 | 1.3E-16 | 0.005 | 0.15 |
| rs2753935 | intron 1 | 93920690 | A | 0.435 | 0.012 | 9.7E-04 | 0.004 | 0.24 |
| rs2144831 | intron 1 | 93919723 | A,C | 0.240 | 0.021 | 9.8E-07 | 0.002 | 0.71 |
| rs709932 | exon 2 | 93918954 | A,C | 0.169 | 0.021 | 1.2E-05 | 0.003 | 0.50 |
| rs6647 | exon 3 | 93917168 | A,C | 0.200 | 0.026 | 7.2E-09 | 0.003 | 0.51 |
| rs17580 (PI S) | exon 3 | 93917015 | D | 0.041 | 0.210 | 1.9E-127 | 0.218 | 1.9E-163 |
| rs28929474 (PI Z) | exon 5 | 93914700 | D | 0.013 | 0.483 | 1.3E-240 | 0.482 | 5.2E-269 |
| rs1303 | exon 5 | 93914596 | A,C | 0.247 | 0.015 | 4.7E-04 | 0.001 | 0.89 |
Abbreviations: AAT, alpha1-antitrypsin; MAF, minor allele frequency; SNP, single nucleotide polymorphism.
Chromosomal position is based on reference panel, NCBI build 36.3.
Includes subjects for whom all the 16 SNPs have been successfully genotyped.
SNP selection was based on extreme trait sequence data (A), tagging SNPs according to HapMap (B), TAMAL software (C) and publication about functionality (D); see Materials and Methods for a more detailed description.
Univariate analyses were adjusted for non-genetic factors only (sex, age, recruiting area and current smoking status). Allele effects are shown in absolute numbers and P<0.005 was considered statistically significant.
In a forward selection approach of stepwise regression, the four SNPs in bold contributed statistically significantly to the variability in AAT serum levels and were included in the final statistical model. Allele effects and p-values refer to this final model.