The results of multiple GWAS studies can be pooled together to perform a meta-analysis. Meta-analysis techniques were originally developed to examine and refine significance and effect size estimates from multiple studies examining the same hypothesis in the published literature. With the development of large academic consortia, meta-analysis approaches allow the synthesis of results from multiple studies without requiring the transfer of protected genotype or clinical information to parties who were not part of the original study approval – only statistical results from a study need be transferred. For example, a recent publication examining lipid profiles was based on a meta-analysis of 46 studies [21]. A study of this magnitude would be logistically difficult (if not impossible) without meta-analysis. Several software packages are available to facilitate meta-analysis, including STATA products and METAL [45], [46].
