CSF MPO concentration was found not to be significantly different in male and female patients at early-stage PD (men, 151 ± 71 pg/mL, n = 12; women, 87 ± 89 pg/mL, n = 10) relative to patients with moderate-advanced PD (men, 141 ± 49 pg/mL, n = 6; women, 68 ± 21 pg/mL, n = 6). The gene discussed is MPO; the disease is Parkinson disease.