This subregion-specific difference in CD68 positive amoeboid microglia was larger in PD patients, with the highest numbers present in the CA2 region (Figure 5c; PD: CA1 vs CA2/CA3/CA4 p < 0.01, CA4 vs CA2/CA3 p < 0.01, CA3 vs CA2 p = 0.278 n.s.; CA1 Mean = 7.0 ± 1.2; CA2 Mean = 37.2 ± 7.2; CA3 Mean = 32.5 ± 6.5; CA4 Mean = 17.5 ± 4.5). This evidence concerns the gene CD68 and Parkinson disease.