Longitudinal changes in salivary biomarkers in Parkinson’s disease (PD) from early (T0) to 4‐year follow‐up (T1), quantified by ELISA: oligomeric and total α‐synuclein, total and phosphorylated tau, MAP1LC3B (autophagy), and TNFa (inflammation). This evidence concerns the gene TNF and Parkinson disease.