We obtained multi-tissue meta-analysis results from the Genotype-Tissue Expression (GTEx) Consortium (V7) and matched variants by position and alleles. We determined which of our significant eGenes were assayed by GTEx from the median TPM results, and determine which genes were expressed in each tissue from the normalized expression matrices. Of the 1329 cis-eQTL eGenes (FDR < 0.05) identified in fetal brain, 176 were either not assayed (115 genes) or had expression values below the cut-off in all tissues (61 genes) in the GTEx study. For a further two fetal eGenes, there were no significant cis-eQTL that were genotyped by GTEx. For each eGene that was included in at least one GTEx expression matrix, we identified the most significant eQTL variant from our analysis that was assayed by GTEx and extracted the meta-analysis results and P values for those eQTLs. For eQTLs that were detected in at least two GTEx tissues, we created a heatmap of m values to show the extent of sharing between fetal brain and adult GTEx tissues. Tissue sharing was also quantified by estimating π1 (the proportion of true positives [30]) among this set of eQTLs in each GTEx tissue.
