HLA-DRB1 and Parkinson disease: Of interest is also that variants of several regulated genes in both PDearly and PDlate samples, including GSTT1 (Wang et al., 2014), CXCR4 (Bonham et al., 2018), BAG3 (Cao et al., 2017) and HLA-DRB1 (Hollenbach et al., 2019), were previously associated with PD.