We then sought to determine the extent of overlap between the mQTLs and the eQTLs in the top Bipolar Disorder associated SNPs. First, we evaluated for (cis) eQTL enrichment in cerebellum among the top Bipolar Disorder associated SNPs. As expected from our earlier study 7 (which was done, however, in transformed lymphocytes), we found a significant excess of locally acting eQTLs in cerebellum among the top SNPs. Again, from 1000 simulated sets, the observed count was 222 while the expected count was 167.9 with standard deviation of 10.9; no simulated set yielded a (cis) eQTL count that matched the observed count for an enrichment p value < 0.001. In contrast, we found no evidence for excess of trans-acting eQTLs (enrichment p = 0.36) in cerebellum among the top Bipolar Disorder associated SNPs. The enrichment we report here does not appear to depend on the 4 Mb definition of cis since the use of a lower threshold (1 Mb) preserves the enrichment robustly (enrichment p < 0.001).
