Cis-eQTL analysis based on these quality-trimmed data and focusing on SNPs located within 50-kb windows around each gene detected the presence of 15,091 statistically significant cis-eQTL associated with 2629 genes (Supplementary Table 1). Twelve of the most significant eQTL are depicted in Figure 1. The MAFs of significant eSNPs were spread widely between 5% and 50%, but the distribution was skewed toward the higher frequencies (Figure 2). The expression traits pertain to many aspects of cellular function from division to antigen processing and presentation. For instance, endoplasmic reticulum aminopeptidase 2 (ERAP2), with the function of trimming antigen peptides in the endoplasmic reticulum for presentation on major histocompatibility complex I, was the strongest expression trait detected in this study.35 Immediately following ERAP2 in significance was X-ray radiation resistance associated 1 (XRRA1). Up-regulated expression of XRRA1 has been linked to reduced capacity for DNA damage repair in human cell lines.36 Overall, Gene Ontology classification based on the molecular function of these 2629 genes indicated that the set was enriched for oxidoreductase and dehydrogenase activity but also for KRAB domain containing zinc finger
