APOE and Alzheimer disease: The key finding of our study is that the PILRA R78G-A allele negatively modifies the effect of APOE and GM17 high-risk variants on AD risk (OR for the GM17 interaction 0.72, 95% CI 0.52–1.00 and OR for the APOE interaction 0.56, 95% CI 0.31–0.98; Table 3 in the discovery cohort).