Meta-analysis of the effect of rs6577641 on mRNA expression levels of SATB1 in the lung*.

*To assess the effect of the SNP rs6577641 on gene expression, a Kruskal-Wallis test was performed. This test generates a p-value, but does not give a direction of the effect. To assess the direction of the effect, a Spearman's correlation test was performed. Next, a Z-score was calculated for each center and a meta-analysis performed for each of the three SATB1 probes across all centers. Finally, a meta-analysis for all three SATB1 probes was performed across all centers. This generated a Z-score of −5.87 and a corresponding p-value of 4.3*10−9, indicating that the susceptibility G allele of the SNP rs6577641 increases SATB1 expression.