Fundamental limit of alpha-synuclein pathology in gastrointestinal biopsy as a pathologic biomarker of Parkinson's disease: Comparison with surgical specimens

Our results demonstrate that AS accumulation identified via pAS IHC of GI biopsies is unreliable due to its low positive rates and poor concordance with surgical specimens, and that future studies investigating AS accumulation in the GI tract should target the stomach, rather than the colon or rectum.