We investigated 8 biological pathways or regions of open chromatin which have previously been associated with PD risk (Figure 1): alpha-synuclein pathway11, adaptive immunity11,12, innate immunity11,12, lysosomal pathway11,13, endocytic membrane-trafficking pathway14, mitochondrial pathway15, microglial open chromatin SNPs27, and monocyte open chromatin SNPs27. This evidence concerns the gene SNCA and Parkinson disease.