Finally, we have attempted to analyze effects in trans by adopting a “candidate variants approach” assigning prior relevance to those SNPs already known to be associated with cis regulation, protein sequence variation (amino acid or splicing variation), or miRNA structure, and this approach made correction by permutation feasible. There were fewer genes exhibiting significant trans effects than exhibiting cis effects. This is a function of the fact that trans effects are often more indirect and therefore weaker, so our sample size does not provide us with enough power in conjunction with the much larger number of tests we have to correct for. In general, the detection of trans effects in humans has been less successful than in yeast 38,39. This may be because the yeast cell comprises the entire organism, so study of the biological interactions in a yeast cell has the potential to detect all of the interactions, while the human cell is just a small part of the organism so many of the intercellular effects mediating trans effects cannot be discovered. Finally, we have provided evidence that among
