We first determined whether there was enrichment of AD association signals from the COGA sample within our significant eQTLs. To that end, we tested the European Americans in the COGA sample (for a set-based enrichment of AD and ARP, i.e. AD case/ status, AD symptom count and maximum number of drinks in 24 hours) with association signals within our eQTLs. Based on this analysis, we observed a significant set-based enrichment for AD diagnosis and AD symptom counts, which also passed the Simes’ correction for multiple testing (adj. p = 0.014 and p = 0.024, respectively). Among the enriched eQTL sets, the most significant GWAS signals in COGA at p≤10−3 were: 1) rs1780705 for neuronatin (NNAT), a mRNA hub gene in M yellow, associated with AD at p = 2.2x10-4, 2) rs13392737 for a long non-coding RNA (PKI55), a mRNA hub gene in M turquoise, associated with AD at p = 1.6x10-4 and 3) rs4243820 for replication protein A2, 32kDa (RPA2), a mRNA hub gene in M turquoise, associated with an AD at p = 4.1x10-4[58, 59].
