The Synuclein-One Study will be evaluating α-synuclein in patients with Parkinson's disease, Multiple System Atrophy, Dementia with Lewy bodies and Pure Autonomic Failure. Using a simple diagnostic test will improve clinical accuracy in diagnosing, earlier diagnosis, and distinguish between neurodegenerative diseases.

Phosphorylated α-synuclein pathology in the diagnosis of synucleinopathies through qualitative and quantitative measurements of cutaneous phosphorylated α-synuclein in patients with Parkinson's disease, Multiple System Atrophy, Dementia with Lewy bodies and Pure Autonomic Failure. An effective tissue biomarker will provide an accurate diagnosis of α-synuclein in clinical practice, will differentiate between synucleinopathies, enable assessment of target engagement in the development of disease modifying and neuroprotective therapies and accelerate the development of neuroprotective and disease modifying therapies.

Inclusion Criteria:

• Male and female between 40-99 years of age
• Prior clinical diagnosis of Parkinson's disease, Multiple System Atrophy, Dementia with Lewy bodies or Pure Autonomic Failure
• Health Subjects, no history of clinical or symptoms suggestive with synucleinopathy

Exclusion Criteria:

• Clinical evidence of severe vascular disease (history of ulceration, poor wound healing, vascular claudication)
• Clinically active coronary artery or cerebrovascular disease
• Current smoker or alcoholism
• History of allergic reaction to local anesthesia for skin biopsies
• Use of blood thinners (aspirin or Plavix alone is allowed)
• Significantly impaired wound healing or history of scarring or keloid formation
• Healthy individuals or individuals with synucleinopathy is disease may be explained by other causes: recent history of encephalitis, Cortical dementia of Alzheimer's type, Whipple's disease, toxin exposure, repeated head injury and stepwise disease progression suggestive of vascular etiology

Eligible men and women, age 40-99 years, will undergo a screening evaluation that includes a thorough medical history, physical and neurologic exam, orthostatic vitals, questionnaires and skin biopsy completed in one visit.

IPD will be shared with researchers that are involved in the study.