Figure 3.

Estimation and Partitioning of SNP Heritability Underlying Gene Expression Variation in African Americans and European Americans

Proportion of variance (PVE; aka SNP heritability) in gene expression levels estimated for all genes (left three plots), genes without detectable eQTLs (middle three plots), and genes with detectable eQTLs (right three plots) in African Americans (A) and European Americans (B). PVE explained by all SNPs is referred to as total PVE (orange), which is partitioned into a component that is explained by cis-SNPs (cis-PVE; green) and another component that is explained by trans-SNPs (trans-PVE; purple). As expected, PVE in eGenes tends to be larger than that in non-eGenes or in all genes. The total PVE as well as the cis-PVE in cis-eQTL genes also tend to be larger than that in non cis-eQTL genes or in all genes.