Table 1 Key providing the full forms of variables used in equations
From: Deriving GWAS summary estimates for paternal smoking in UK biobank: a GWAS by subtraction
Variable initial | Manuscript section | Full form | Contribution to analyses |
|---|---|---|---|
Bcg-cp | Derivation of the linear model | The association between the child’s genotype and child’s phenotype (i.e. his/her genetic liability towards the phenotype) | This is estimated from a GWAS of smoking. Paternal smoking summary statistics are derived by subtracting Bcg-mg from this variable |
Bfg-fp | The association between the father’s genotype and father’s phenotype | NA | |
Bmg-mp | The association between the mother’s genotype and the mother’s phenotype | NA | |
Bcg-fp | The association between the child’s genotype and the father’s phenotype | This is the target estimand of the WLM | |
Bcg-fg | The association between the child’s genotype and the father’s genotype | NA | |
Bcg-mp | The association between the child’s genotype and the mother’s phenotype | This is estimated from a GWAS of maternal smoking. Paternal smoking summary statistics are derived by subtracting this variable from Bcg-cp | |
Bcg-mg | The association between the child’s genotype and the mouther’s genotype | NA | |
\({SE}_{\mathrm{cg}-\mathrm{fp}}\) | Standard error in the estimate of Bcg-fg | Uncertainty in WLM estimates | |
\({SE}_{\mathrm{cg}-\mathrm{cp}}^{2}\) | Standard error in the estimate of Bcg-cp | Uncertainty in the estimates from the smoking GWAS | |
\({SE}_{\mathrm{cg}-\mathrm{mp}}^{2}\) | Standard error in the estimate of Bcg-mp | Uncertainty in the estimates from the maternal smoking GWAS | |
Fi | Validation situation | Allele inherited from the father | NA |
Mi | Allele inherited from the mother | NA | |
Cg | Child’s unweighted allele score | Exposure in all GWASs | |
B | Variant-phenotype association (i.e. allele score weights) | NA | |
Cp | Child’s phenotype | Outcome in GWAS of smoking | |
Mg | Maternal allele score (i.e. with both inherited and non-inherited allele) | NA | |
Mp | Mather’s phenotype | Outcome in GWAS of maternal smoking | |
Fp | Father’s phenotype | Outcome in the traditional GWAS of paternal smoking |