I determined bootstrap P thinking for the Q
x statistic (73) by recomputing the statistic for random sets of SNPs in matched 5% derived allele frequency bins (polarized using the chimpanzee reference gnome panTro2). For each bootstrap replicate, we keep the original effect sizes but replace the frequencies of each SNP with one randomly sampled from the same bin. Unlike the PRS calculations, we ignored missing data, since the Qx statistic uses only the population-level estimated allele frequencies and not individual-level data. We tested a series of nested sets of SNPs (x axis in Fig. 5), adding SNPs in 100 SNP batches, ordered by increasing P value, down to a P value of 0.1.
Artificial GWAS Analysis.
We simulated GWAS, generating causal effects at a subset of around 159,385 SNPs in the intersection of SNPs, which passed QC in the UK Biobank GWAS, are part of the 1240 k capture, and are in the POBI dataset (84). We assumed that the variance of the effect size of an allele of frequency f was proportional to [f(1 ? f)] ? , where the parameter ? measures the relationship between frequency and effect size (85). We performed 100 simulations with ? = ?1 (the most commonly used model, where each SNP explains the same proportion of phenotypic variance) and 100 with ? = ?0.45 as estimated for height (85). We then added an equal amount of random noise to the simulated genetic values, so that the SNP heritability equaled 0.5. We tested for association between these SNPs and the simulated phenotypes. Using these results as summary statistics, we computed PRS and Qx tests using the pipeline described above.
Level is highly heritable (ten ? ? ? –14) and this amenable to help you genetic research by GWAS. With shot versions off thousands of somebody, GWAS has actually known thousands of genomic versions that will be notably relevant towards the phenotype (fifteen ? Continue Reading