The penetrance of genetic variation has been assumed to be higher at the level of neural phenotypes than at the level of behavioral phenotypes. One of the few attempts to validate this assumption is the study of Rose and Donohoe published in this issue. In this article, we will address 2 methodological issues we believe have to be considered for a better understanding of the present results. We briefly discuss potential solutions that might also help improve future meta-analyses of effect sizes in neuroimaging data.