We believe that the answer to both questions is “no”, or at least that it is incumbent upon our researcher and others pursuing this type of research to demonstrate otherwise. Although this particular example is hypothetical, this type of situation does in fact occur, which illustrates a difficulty that candidate gene studies can create even when they yield positive findings because the base rate expectation that those findings are actually false is extremely high. We argue in the next section that GWASs are clearly preferable to candidate gene studies, and we advocate a different approach to selecting candidate variants in section 10.3. We propose here that researchers should attempt to replicate a candidate gene-endophenotype association in an independent sample within the same report, reporting the meta-analytic effect size and p-value corrected for multiple testing as appropriate. That way, both positive and negative findings are more credible than they would be if based on a single sample.
