A comprehensive examination of the early diagnostic markers, the accumulation of alpha-synuclein, the impacts of neurotoxins on ICC, the distribution and functionality of ICC, conflicting autopsy reports, neurohumoral signaling, therapeutic targets, impacts of medication, and alterations in the microbial composition and dysbiosis is imperative for individuals with PD. The gene discussed is SNCA; the disease is intrahepatic cholangiocarcinoma.