We examined the overlap between the cis eQTLs identified in the present study and those found in three previous association studies in which gene expression was explored in LCLs [1], [2] and hepatic cells [3]. For this comparison, a significance threshold of 3.9×10−6 (Bonferroni-corrected for 12,808 genes) was used for the analysis of eQTLs in GHS data, corresponding to a single hypothesis tested per gene. Among the cis eQTLs considered significant in each of the studies and involving expression traits detected in GHS, 66.7%, 56.5% and 54.1%, respectively, were significant in our data ( Table 3 , Files S2–S4). The proportion of cis eQTLs that replicated in GHS increased with the increasing level of significance reported in each study, consistent with the fact that stronger associations are more robust and more likely to be shared by different types of cells. These comparisons revealed a relatively high rate of replication of the previous findings in GHS. However, as a consequence of its greater power, P-values observed in GHS were considerably lower than those previously reported ( Figure 2 ).
