Another possible approach to saving on genotyping costs is DNA pooling, at least for an initial screen, to be followed by individual genotyping of promising loci100. Beyond the technical challenges in forming comparable pools and assaying allelic concentrations, this approach would be feasible for studies of G×E interactions only if the pools were stratified on the basis of exposure, thus limiting the number of possible environmental factors that could be considered. Recent advances in DNA bar-coding101, however, would permit the reconstruction of individual genotypes from within pools, thereby allowing a broader range of interaction analyses102.
