Spearman analyses revealed significant positive correlations between MPO and PAR concentrations in the putamen of both AD patients with the TSPO (rs6971) GG genotype (rs = 0.806, p = 0.005) and PDD patients with the TSPO (rs6971) AG genotype (rs = 0.900, p = 0.037) (Figure 1d). Here, MPO is linked to Alzheimer disease.