Our observation that sets of independent SNPs, associated with the same complex phenotype sometimes also affect exactly the same trans-gene, further substantiates the validity of our findings. Based on the reported effect-sizes of these variants on these complex phenotypes, we have shown here that the individual effects of these SNPs on trans-gene expression can often be stronger. This suggests that these down-stream gene expression effects do not fully propagate to the eventual phenotype and are somehow buffered. This ‘phenotypic buffering’ has been observed before in plants [44] and suggests that additional compensatory mechanisms exist that control these complex phenotypes. However, we do realize that accurate estimates on this phenomenon requires the availability of both gene-expression and phenotype data for these traits. As we did not have these phenotypes for our samples, we relied upon estimates from literature. Future studies that have collected both genome-wide genotype, expression and phenotype data from the same individuals will permit answering the question what the extent of this phenotypic buffering is. We should emphasize that the number of converging pairs of SNPs that we identified
