We found that PD patients presented higher allele frequencies of HLA-DRB1*0301 (0.0869 vs. 0.0477, p = 0.001 in series 1, 0.0699 vs. 0.0391, p = 0.025 in series 2, 0.0811 vs. 0.0449, p = 9.728E-5 in combined series 1 and series 2), DRB1*0403 (0.0307 vs. 0.0159, p = 0.035 in series 1), DRB1*1202 (0.1123 vs. 0.0875, p = 0.045 in series 1), DRB1*1312 (0.0187 vs. 0.0080, p = 0.044 in series 1), and DRB1*1454 (0.0428 vs. 0.0209, p = 0.035 in series 1) than the healthy controls. This evidence concerns the gene HLA-DRB1 and Parkinson disease.