Expression QTL results can be used to prioritize genes in a region of association before undertaking laborious and expensive analysis in animal models and other systems (Teslovich et al. 2010). Current results suggest that many eQTLs could be shared across tissues (Ding et al. 2010) and that constructing a comprehensive catalog may increase the chances of capturing relevant transcripts for diseases that primarily affect particular organs and for which the relevant transcripts are only incidentally expressed in blood. Tissue-specific eQTLs nevertheless remain the gold standard when they are not limited by availability of appropriate biological samples.
