Compared to the control group, DDC was significantly elevated in each atypical Parkinsonian subgroup (PSP: F2,367 = 8.2, PBonferroni-corrected = 8.7 × 10−7; MSA: F2,354 = 8.5, PBonferroni-corrected = 1.1 × 10−6; CBS: F2,348 = 3.3, PBonferroni-corrected = 3.3 × 10–3). The gene discussed is CBS; the disease is multiple system atrophy.