Despite these concerns, some Think Tank participants suggested adjusting GWAS thresholds to account for the number of exposures as an approach for considering an interaction “established” based on statistical evidence in GEWIS. One number proposed was 10−10. This number assumes 100 exposures, and some participants questioned if that was a realistic assumption, or if it was an overestimate leading to too stringent of a threshold. Participants felt strongly that if a threshold is adopted, it should not create a barrier to publication for GxE. We should not conflate what is publishable with truth. As has been noted previously [Ghazarian, et al. 2013; Mechanic, et al. 2012], it is important to have publication or reports of data from well-designed studies that have been properly analyzed but did not achieve statistical significance, and the group supported a web-based clearinghouse or repository for results of putative interactions while more evidence is being collected. There is current concern that many initial examinations of GEWIS are “sitting in desk drawers”. Additionally, if a threshold is chosen, it should not be viewed as replacing or superseding replication in an independent population. However, as discussed below, there are special challenges in replication for GxE interactions.
