Abstract
Many common human traits are believed to be a composite reflection of multiple genetic and non‐genetic factors and the genetic contribution is consequently often difficult to characterise. Recent advances suggest that subtle variation in the regulation of gene expression may contribute to complex human traits. In two reports,1,2 Cheung and colleagues scale up human genetics analysis to an impressive level in a genome‐wide search for the regulators of gene expression. They perform linkage analysis on expression profiles for over 3,500 genes and then employ the HapMap resource3 to take positive findings through to association studies at the genome‐wide level. This work gives new insights into the complexities of gene regulation and the plausibility of genome‐wide study design. BioEssays 28: 968–972, 2006. © 2006 Wiley Periodicals, Inc.