Results revealed significant associations between MoCA and t-tau (β = 0.0086; P = 0.0362) in PDCU; α-syn and MoCA (β = −0.0090; P = 0.0037) in PDCI; and SDMT and Aβ1–42 (β = 0.0042; P = 0.0391) in PDCI, but not in all participants with PD. The gene discussed is DOCK3; the disease is Parkinson disease.