CPE and Parkinson disease: In prefrontal cortex neurons, we observed 70 differentially methylated sites affecting 58 genes in PD (1.2 differentially methylated sites per affected ALP gene with average methylation change 8% in CpG and 6% in CpH sites; q < 0.05, robust linear regression; Fig. 2a; Supplementary Data 4), which again were mostly hypermethylated (OR = 2.41, p = 7.13 × 10−4, Fisher’s exact test; Fig. 2b, PFC).