Most existing expression quantitative trait locus (eQTL) mapping studies have been focused on individuals of European ancestry, but are underrepresented in other populations including populations with African ancestry. In this study, we fill this critical knowledge gap by performing a large-scale in-depth eQTL mapping study on 1,032 African Americans (AA) and 801 European Americans (EA) in the GENOA cohort. Our result suggesting potentially diverse genetic architecture underlying expression variation in the two populations. Finally, the large sample sizes in GENOA allow us to construct accurate expression prediction models in both AA and EA, facilitating powerful transcriptome wide association studies. Overall, our results represent an important step towards revealing the genetic architecture underlying expression variation in African Americans. 

The cis-eQTL mapping summary statistics could be found at http:https://xzlab.org/data.html

The gene expression data used in this analysis is available at the Gene Expression Omnibus (GEO Study Accession: GSE138914 for AA; GSE49531 for EA).

The SNP data is available from the Database of Genotypes and Phenotypes (dbGaP Study Accession: phs001238.v2.p1).

Data can also be obtained from the corresponding author on reasonable request.