STX4 and Parkinson disease: In the first, Tewhey et al.60 employed multiplexed reporter assays to investigate the downstream effects of GWAS risk variants across several traits including PD, reporting an association between the PD risk variant, rs11865038, and expression of STX4. In the second study, STX4 was identified as a common risk gene for AD and PD through a transcriptome-wide association study (TWAS)61.