ATP13A2 and Parkinson disease: Across all three regions examined (anterior cingulate, parahippocampal and occipital cortices), there was a significant positive correlation between membrane-associated ATP13A2 and total ATP13A2 levels (R = 0.67, p < 0.0001; Additional file 1: Figure S1A), while significant negative correlations were observed between membrane-associated α-synuclein and both membrane-associated (R = −0.31, p = 0.04) and total (R = −0.56, p < 0.0001) ATP13A2 levels in the PD, DLB and control cases (Figure 1C).