We have established clear patterns underlying heritability of steady-state gene peripheral blood transcription, and demonstrated strong connections to disease annotation. The use of peripheral blood enables further investigation to immune-related diseases,63 but may also be useful for other tissues. For example, there were 78 genome-wide significant loci for inflammatory bowel disease (IBD) in cohorts genotyped with the custom “immunochip”. In 10 of 78 instances, there was near perfect overlap of the local eQTL results from this study with the IBD association (excludes numerous other regions which overlapped but not as precisely, B Bulik-Sullivan and M Daly, personal communication). These results supply mechanistic hypotheses that can be evaluated in subsequent experiments. In comparisons across four mouse tissues, we found that genes expressed in multiple tissues tended to have cis regulatory elements.64
