ELANE and Parkinson disease: By employing pair comparisons for assessing biomarkers of early-stage disease and/or disease progression, we here also provide evidence that circulating levels of TYRA may be a promising, highly sensitive and specific (power >0.80), marker for early detection of PD, while those of TYRA, NE, and TYRO may cumulatively constitute putative markers of disease progression (power >0.80).