CXCR4 and Parkinson disease: At a conjunction FDR < 0.05, we identified 2 SNPs that were associated with increased risk for both PSP and PD (Table 2, Fig. 1b): rs749873 (intergenic; closest gene = CXCR4, on chr2, minimum conjunction FDR = 0.01; Supplemental Fig. 1a) and rs11012 (UTR-3; closest gene = PLEKHM1 within MAPT region on chr 17, PSP p-value = 4.9 × 10−39, minimum conjunction FDR = 9.3 × 10−9).