This study aims to validate an objective pathological test for synucleinopathies using ?-synuclein accumulation in skin punch biopsies. The study will contribute to the development of accurate and minimally invasive diagnostic tools for early detection of synucleinopathies, potentially improving patient outcomes and treatment interventions. Furthermore, we aim to demonstrate that skin biopsies provide a reliable method to quantify P-SYN levels in patients with PD. This could offer significant advantages as ongoing trials with anti-synuclein therapies lack a method to measure P-SYN in humans.