Here, we also provided further evidence by showing that PD patients carrying the APOE ε4 allele presented with lower levels of CSF Aβ42 (p = 3.8 × 10−06), higher MCBP (p = 5.80 × 10−08) and higher Braak Aβ scores (p = 4.40 × 10−04). This evidence concerns the gene APOE and Parkinson disease.