PD: Parkinson's disease; SCFA: short-chain fatty acid; H. pylori: Helicobacter pylori; CRP: C-reactive protein; UPDRS: Unified Parkinson's Disease Rating Scale; CNS: central nervous system; ENS: enteral nervous system; FMT: fecal microbiota transplant; VLDL; very-low-density lipoprotein; HDL: high-density lipoprotein. This evidence concerns the gene CRP and Parkinson disease.