Female PD patients, compared to males, had lower E2 and TT levels (0.5 ± 0.5 vs. 28.6 ± 16.9, p < 0.001, and 26.5 ± 19.8 vs. 484.8 ± 182.9, p < 0.001, respectively), and higher gonadotropins levels (FSH 64.9 ± 26.5 vs. 8.6 ± 12.3, p < 0.001, and LH 22.6 ± 10.5 vs. 3.7 ± 2.9, p < 0.001, respectively). This evidence concerns the gene PLOD1 and Parkinson disease.