📗 Cite This Artifact
Biomarkers for Parkinson's Disease
Biomarkers for Parkinson's Disease
Overview
Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, affecting approximately 1-2% of the population over 65 years of age and up to 4% of those over 85. The disease is characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, leading to the characteristic motor symptoms of tremor, bradykinesia, rigidity, and postural instability. However, non-motor symptoms including cognitive impairment, autonomic dysfunction, sleep disorders, and mood disturbances often precede motor signs by years or even decades. [@fairfoul2016]
The development of PD biomarkers has been driven by several clinical needs: earlier diagnosis before substantial neuron loss occurs, disease progression monitoring, identification of disease-modifying therapy targets, and patient stratification for clinical trials. Unlike Alzheimer's disease, where amyloid and tau biomarkers have transformed diagnosis, PD biomarker development has focused on multiple modalities including alpha-synuclein, neuroimaging, and genetic markers. [@norris2019]
Pathway Diagram
...
Biomarkers for Parkinson's Disease
Overview
Parkinson's disease (PD) is the second most common neurodegenerative disorder after Alzheimer's disease, affecting approximately 1-2% of the population over 65 years of age and up to 4% of those over 85. The disease is characterized by progressive loss of dopaminergic neurons in the substantia nigra pars compacta, leading to the characteristic motor symptoms of tremor, bradykinesia, rigidity, and postural instability. However, non-motor symptoms including cognitive impairment, autonomic dysfunction, sleep disorders, and mood disturbances often precede motor signs by years or even decades. [@fairfoul2016]
The development of PD biomarkers has been driven by several clinical needs: earlier diagnosis before substantial neuron loss occurs, disease progression monitoring, identification of disease-modifying therapy targets, and patient stratification for clinical trials. Unlike Alzheimer's disease, where amyloid and tau biomarkers have transformed diagnosis, PD biomarker development has focused on multiple modalities including alpha-synuclein, neuroimaging, and genetic markers. [@norris2019]
Pathway Diagram
Core PD Pathological Mechanisms
Alpha-Synuclein Pathology
Alpha-synuclein (SNCA) is the central protein in PD pathogenesis:
Normal Function:
- Presynaptic protein involved in synaptic vesicle trafficking
- Regulates neurotransmitter release
- May have chaperone function
- Misfolded alpha-synuclein forms toxic oligomers
- Oligomers seed the formation of fibrils
- Fibrils aggregate into Lewy bodies
- Lewy bodies are the pathological hallmark of PD [@spillantini1997]
- Pathology spreads in a characteristic pattern
- May propagate via prion-like mechanisms
- Braak staging describes progression from brainstem to cortex
Dopaminergic Neuron Loss
substantia Nigra Degeneration:
- Loss of dopaminergic neurons in substantia nigra pars compacta
- Reduced dopamine in striatum
- Motor symptoms correlate with >50% neuron loss
- Mitochondrial dysfunction
- Oxidative stress
- [Neuroinflammation](/mechanisms/neuroinflammation)
- [Apoptosis](/mechanisms/apoptosis)
- Impaired autophagy
Neuroinflammation
Microglial activation is a prominent feature:
- Activated microglia in substantia nigra
- Pro-inflammatory cytokines elevated
- May be both cause and consequence of neurodegeneration
- TREM2 variants affect PD risk [@mendes2019]
Biomarker Categories and Mechanistic Mapping
Alpha-Synuclein Biomarkers
CSF Alpha-Synuclein
Total Alpha-Synuclein:
- Reduced in PD vs. controls
- Reflects neuronal loss
- Sensitivity ~70%, specificity ~60%
- Lower levels correlate with disease progression [@hall2012]
- Elevated in PD
- More disease-specific than total
- Ratio of oligomer/total may be diagnostic
- Reflects toxic species
- pSer129 is the major pathological form
- Elevated in PD CSF
- Very high specificity (>90%)
- Correlates with disease severity [@fujiwara2013]
Alpha-Synuclein in Blood
Plasma/Serum Measurement:
- More accessible than CSF
- Technical challenges with assay sensitivity
- Total alpha-synuclein: reduced in PD
- Oligomeric alpha-synuclein: elevated
Skin/Biopsy Markers
Subcutaneous Nerve Biopsy:
- Detection of phosphorylated alpha-synuclein in nerves
- ~70% sensitivity in PD
- May enable early diagnosis
- Emerging as clinical tool
Neurodegeneration Biomarkers
Neurofilament Light Chain (NfL)
CSF NfL:
- Elevated in PD compared to controls
- Reflects axonal damage
- Correlates with disease progression
- Higher levels predict faster progression [@lin2018]
- Excellent correlation with CSF NfL
- Elevated in PD vs. controls
- Predicts progression
- Useful for clinical monitoring
Tau Protein
CSF Total Tau:
- Moderately elevated in PD
- Less specific than in AD
- May reflect neurodegeneration
- Generally normal in PD
- Helps distinguish from AD
- Useful for differential diagnosis
Neuroimaging Biomarkers
Dopamine Transporter Imaging
DaTscan (FP-CIT SPECT):
- Measures dopamine transporter binding
- Reduced in PD
- Supports diagnosis
- Distinguishes PD from essential tremor
- Reflects presynaptic dopaminergic neuron integrity
- Correlates with motor severity
- Helps rule out non-degenerative mimics [@benamer2000]
PET Imaging
FDG-PET:
- Shows characteristic metabolic pattern in PD
- Reduced metabolism in basal ganglia
- Correlates with disease progression
- May show treatment effects [@eidelberg2009]
- Measures vesicular monoamine transporter
- Reduced in PD
- Direct measure of dopaminergic terminals
MRI
Structural MRI:
- May show subtle changes in substantia nigra
- Normal in early PD
- More useful for differential diagnosis
- DTI changes in substantia nigra
- May aid early diagnosis
- Research tool primarily
- Detects neuromelanin in substantia nigra
- Signal reduced in PD
- Emerging clinical tool
Genetic Biomarkers
Risk Genes
| Gene | Variant | Risk Effect | Function |
|------|---------|-------------|----------|
| SNCA | Multiplications | Increased | Alpha-synuclein expression |
| LRRK2 | G2019S | Increased | Protein kinase |
| GBA | Various | Increased | Lysosomal glucocerebrosidase |
| PARK2 (Parkin) | Recessive | Early-onset | Ubiquitin ligase |
| PINK1 | Recessive | Early-onset | Mitophagy kinase |
| DJ-1 | Recessive | Early-onset | Oxidative stress response |
G2019S LRRK2
- Most common genetic cause of PD
- Autosomal dominant
- ~5-10% of PD patients (population dependent)
- Associated with typical late-onset PD
- Higher penetrance with age [@healy2008]
GBA Variants
- Heterozygous variants increase PD risk 5-6 fold
- Associated with earlier onset
- More severe cognitive involvement
- Important for genetic counseling [@sidransky2009]
TREM2 and Genetic Risk
TREM2 Variants:
- R47H variant increases PD risk
- Affects microglial function
- Links neuroinflammation to PD risk
Protein Biomarkers
Clusterin
CSF Clusterin:
- Elevated in PD
- May reflect alpha-synuclein pathology
- Potential for progression prediction
Beta-Glucocerebrosidase (GCase) Activity
GCase Activity:
- Reduced in PD vs. controls
- More severe in GBA carriers
- May reflect lysosomal dysfunction
Metabolic Biomarkers
Homocysteine
Elevated Homocysteine:
- Common in PD
- Associated with cognitive impairment
- May be complication of treatment
Uric Acid
Uric Acid:
- Antioxidant
- Higher levels associated with lower PD risk
- May have neuroprotective effect
- Lower in PD patients [@weisskopf2015]
Autonomic Biomarkers
Cardiac MIBG Imaging
MIBG Scintigraphy:
- Measures cardiac sympathetic innervation
- Reduced uptake in PD
- Helps distinguish PD from PSP/CBS
- Reflects autonomic dysfunction
Skin Sympathetic Function
Testing:
- Quantitative sudomotor axon reflex test (QSART)
- Shows autonomic involvement
- May help identify PD subtypes
Emerging Biomarkers
Blood-Based Biomarkers
Exosome Biomarkers:
- Neuronal-derived exosomes contain alpha-synuclein
- pSer129 in exosomes: promising marker
- Under clinical validation
- Elevated in neurodegeneration
- May reflect neuronal loss
- Technical challenges
Salivary Biomarkers
Alpha-Synuclein in Saliva:
- Total alpha-synuclein: elevated in PD
- Oligomeric: potentially more specific
- Non-invasive sampling
Tear Biomarkers
Tear Fluid Analysis:
- Alpha-synuclein detection
- Emerging research
- Non-invasive
Olfactory Biomarkers
Olfactory Testing:
- Olfactory dysfunction is early sign
- Olfactory testing aids diagnosis
- May identify pre-motor PD
Clinical Applications
Diagnosis
Diagnostic Criteria:
- UK Brain Bank criteria still used
- Clinical diagnosis supported by biomarkers
- DaTscan for uncertain cases
| Scenario | Recommended Biomarkers |
|----------|----------------------|
| Typical PD | DaTscan, clinical exam |
| Atypical features | MRI, MIBG |
| Early/uncertain | Olfactory testing, DaTscan |
| Family history | Genetic testing |
Prognosis
Progression Markers:
- NfL: predicts progression rate
- pSer129: correlates with severity
- Motor scores over time
- Elevated NfL predicts dementia
- GBA variants: cognitive risk
- REM sleep behavior disorder: cognitive risk
Clinical Trial Enrichment
Patient Selection:
- Genetic stratification
- Biomarker inclusion criteria
- Disease stage matching
- NfL as progression marker
- Imaging endpoints
- Motor assessments
Biomarker Integration
The PD Biomarker Framework
| Category | Biomarkers | Mechanism |
|----------|-----------|------------|
| Alpha-synuclein | CSF total, oligomer, pSer129 | Protein pathology |
| Neurodegeneration | NfL, tau | Neuronal loss |
| Imaging | DaTscan, FDG-PET | Functional changes |
| Genetics | LRRK2, GBA, SNCA | Risk/molecular subtype |
Disease Stage Patterns
Pre-motor PD:
- Olfactory dysfunction
- REM sleep behavior disorder
- Autonomic dysfunction
- DaTscan abnormality
- Subtle motor signs
- Possibly elevated NfL
- Multiple biomarker abnormalities
- Progressive changes
- Motor and non-motor symptoms
Cross-Linking to Related Mechanisms
PD biomarkers connect to numerous pathways:
- [Alpha-Synuclein Pathology](/mechanisms/alpha-synuclein) - Core pathology
- [Mitochondrial Dysfunction](/mechanisms/mitochondrial-dysfunction) - Energy failure
- [Neuroinflammation](/mechanisms/neuroinflammation-across-neurodegeneration) - Microglial activation
- [Oxidative Stress](/mechanisms/oxidative-stress-neurodegeneration) - ROS damage
- [Protein Aggregation](/mechanisms/protein-aggregation) - Aggregation pathways
- [Autophagy Dysfunction](/mechanisms/autophagy-lysosomal-pathways) - Lysosomal impairment
- [Neurodegeneration Overview](/mechanisms/neurodegeneration-overview) - General mechanisms
- [Dopamine Signaling](/mechanisms/dopamine-signaling-pathway) - Dopamine pathways
- [LRRK2 Pathway](/mechanisms/lrrk2-pathway) - LRRK2 biology
- [GBA Pathway](/mechanisms/gba-glucocerebrosidase) - GBA connections
Biomarker Validation and Standardization
Current Status
Validated Biomarkers:
- DaTscan: clinically approved
- Genetic testing: widely available
- Olfactory testing: established
- CSF alpha-synuclein species
- NfL in blood
- Neuroimaging markers
Challenges
Standardization:
- Assay harmonization needed
- Reference values vary by assay
- Sample handling protocols
- Overlap with other disorders
- Need for disease-specific markers
- Biomarker combinations improve specificity
Multi-Center Studies
Ongoing Studies:
- Parkinson's Progression Markers Initiative (PPMI)
- Michael J. Fox Foundation biomarkers
- Large cohort studies
Future Directions
Biomarker Development Priorities
Near-term Goals:
- Blood-based alpha-synuclein validation
- Progression biomarkers
- Treatment response markers
- Pre-motor detection
- Personalized medicine
- Real-time monitoring
Emerging Technologies
Digital Biomarkers:
- Smartphone-based assessments
- Wearable movement sensors
- Voice analysis
- Single-molecule detection
- Seed amplification assays
- Multi-omics approaches
Therapeutic Monitoring
Treatment Response Biomarkers
Current Markers:
- Clinical motor scales
- Imaging (DaTscan) for progression
- NfL for neurodegeneration
- Target engagement biomarkers
- Mechanism-specific markers
Disease-Modifying Therapy Markers
Needed Markers:
- Alpha-synuclein lowering
- Neuroprotection markers
- Neuronal health biomarkers
Biomarker Comparisons
PD vs. Atypical Parkinsonism
Progressive Supranuclear Palsy (PSP):
- PSP: normal MIBG
- PSP: elevated p-tau
- PSP: different FDG pattern
- MSA: normal MIBG (often)
- MSA: different imaging pattern
- MSA: more rapid progression
PD vs. AD
| Marker | PD | AD |
|--------|-----|-----|
| Core protein | α-synuclein | Amyloid, tau |
| NfL | Elevated | Elevated |
| p-tau | Normal | Elevated |
| Imaging | DaTscan | Amyloid PET |
Deep Dive: Alpha-Synuclein Biology and Biomarkers
Structure and Function of Alpha-Synuclein
Alpha-synuclein is a 140-amino acid protein encoded by the SNCA gene. The protein consists of three domains:
N-Terminal Domain:
- Contains seven repeats of 11 residues each
- Binds to lipid membranes
- Predisposed to aggregation
- Contains mutations linked to familial PD (A30P, A53T, E46K)
- Non-Aβ component of amyloid plaques
- Highly hydrophobic
- Critical for aggregation
- Forms the core of Lewy bodies
- Acidic region
- Chaperone-like activity
- May regulate aggregation
Mechanisms of Aggregation
Oligomer Formation:
- Initial step: monomers → oligomers
- Toxic oligomers are the most damaging species
- Membrane permeabilization by oligomers
- Transfer between cells
- Oligomers seed fibril formation
- Beta-sheet rich fibrils
- Incorporated into Lewy bodies
- Less toxic than oligomers
- Prion-like propagation hypothesis
- Exosomal release
- Uptake by neighboring neurons
- Templated misfolding [@spillantini1997]
Seed Amplification Assays
Real-Time Quaking-Induced Conversion (RT-QuIC):
- Detects minute amounts of abnormal alpha-synuclein
- High sensitivity and specificity for PD
- Can detect in CSF, blood, tissue
- Emerging clinical tool [@fairfoul2016]
- Similar principle to RT-QuIC
- Detects oligomeric species
- Research and clinical applications
Alpha-Synuclein in Different Compartments
Cerebrospinal Fluid:
- Most extensively studied compartment
- pSer129 is most specific
- Oligomers reflect disease state
- More accessible but technical challenges
- Total alpha-synuclein lower in PD
- Oligomeric species more specific
- Exosome-derived protein
- Non-invasive sampling
- Total protein elevated in PD
- Requires further validation
- Novel approach
- Preliminary results promising
- More research needed
- Subcutaneous biopsy
- pSer129 in autonomic nerves
- May confirm diagnosis
Detailed Mechanisms of Neuronal Loss
Mitochondrial Dysfunction
Complex I Deficiency:
- Reduced complex I activity in PD substantia nigra
- Leads to ATP deficiency
- Increased ROS production
- Seen in sporadic and genetic PD
- PINK1 accumulates on damaged mitochondria
- Recruits Parkin for mitophagy
- Loss-of-function mutations cause early-onset PD
- Failure of mitophagy leads to accumulation of damaged mitochondria [@norris2019]
- GBA encodes glucocerebrosidase
- Lysosomal dysfunction leads to alpha-synuclein accumulation
- GBA variants increase PD risk
- Reciprocal relationship: alpha-synuclein impairs GBA
Oxidative Stress
Sources of ROS:
- Mitochondrial dysfunction
- Dopamine oxidation
- [Neuroinflammation](/mechanisms/neuroinflammation)
- Environmental toxins
- Glutathione depletion in PD
- Reduced superoxide dismutase activity
- Elevated oxidative stress markers
- Lipid peroxidation
- Protein oxidation
- DNA damage
- Neuronal death
Neuroinflammation
Microglial Activation:
- Chronic activation in PD substantia nigra
- Pro-inflammatory cytokines (TNF-α, IL-1β, IL-6)
- NADPH oxidase activation
- Oxidative burst
- Receptor on microglia
- Variants affect PD risk
- Modulates phagocytosis
- May have dual roles
Impaired Autophagy
Macroautophagy:
- Reduced in PD
- Contributes to protein aggregate accumulation
- Damaged mitochondria not cleared
- Lysosomal dysfunction plays role
- Declines with age
- Important for alpha-synuclein degradation
- Impairment leads to accumulation
LRRK2 Biology and Biomarkers
LRRK2 Function
Kinase Activity:
- Leucine-rich repeat kinase 2
- GTPase and kinase domains
- Phosphorylates multiple substrates
- Role in membrane trafficking
- G2019S: most common
- Increased kinase activity
- Variable penetrance
- Typical PD phenotype
Biomarker Implications
Kinase Activity Markers:
- Direct measurement challenging
- Autophosphorylation sites
- Substrate phosphorylation
- LRRK2 inhibitors in development
- Biomarkers for target engagement
- Stratification for trials
GBA and Lysosomal Biomarkers
GBA Biology
Normal Function:
- Glucocerebrosidase
- Degrades glucosylceramide
- Localized to lysosomes
- Heterozygous variants increase risk
- Reduced enzyme activity
- Leads to alpha-synuclein accumulation
- More severe phenotype
Biomarker Implications
GCase Activity:
- Reduced in PD
- More reduced in carriers
- Potential biomarker
- Other lysosomal enzymes
- May be generally affected
Imaging Biomarkers: Detailed Mechanisms
Dopamine Transporter Imaging
Mechanism:
- SPECT tracers (FP-CIT, ¹²³I-FP-CIT)
- Bind to dopamine transporter
- Reflect presynaptic terminals
- Reduced in PD
- Supports diagnosis
- Distinguishes from essential tremor
- Early detection possible
- Progression monitoring [@benamer2000]
FDG-PET Patterns
PD-Specific Pattern:
- Increased pallidal metabolism
- Reduced putaminal metabolism
- Cerebellar involvement in progression
- Network-based analysis
- Differential diagnosis
- Progression monitoring
- Treatment response [@eidelberg2009]
Neuromelanin MRI
Mechanism:
- Neuromelanin in substantia nigra
- Paramagnetic properties
- Signal reduction in PD
- Non-invasive
- No radiation
- Emerging tool
Diffusion Tensor Imaging
Changes in PD:
- Reduced FA in substantia nigra
- Reflects microstructural changes
- May aid early diagnosis
Genetic Subtypes and Biomarkers
LRRK2 PD
Clinical Features:
- Typical late-onset PD
- Often tremor-dominant
- Good response to dopaminergic therapy
- Same biomarkers as sporadic PD
- May have slower progression
- Kinase activity markers (research)
GBA PD
Clinical Features:
- Earlier onset
- More cognitive impairment
- Faster progression
- Lower GCase activity
- Potentially elevated biomarkers
- More aggressive disease
SNCA Multiplication
Clinical Features:
- Early onset
- Rapid progression
- Often with dementia
- Very elevated alpha-synuclein
- More severe pathology
- Distinct biomarker pattern
Biomarker Combinations for Clinical Use
Diagnostic Algorithms
Algorithm 1: Typical PD:
Algorithm 2: Early PD:
Algorithm 3: Atypical Features:
Prognostic Algorithms
Cognitive Progression:
- Baseline NfL
- GBA status
- REM sleep behavior disorder
- Age
- Baseline NfL
- Disease duration
- Motor phenotype
- Treatment response
Cost and Accessibility
Economic Considerations
Testing Costs:
- Genetic testing: moderate cost
- Imaging: expensive
- CSF biomarkers: variable
- Academic centers: comprehensive
- Community: limited
- Blood vs. CSF: different access
Implementation Barriers
Standardization:
- Multiple assay platforms
- Cut-off values vary
- Reference populations
- Provider education
- Interpretation guidelines
- Reimbursement
Clinical Trial Applications
Patient Stratification
Biomarker-Based Selection:
- Genetic stratification
- Disease stage matching
- Biomarker eligibility criteria
- Tremor-dominant vs. PIGD
- Cognitive phenotype
- Rate of progression
Endpoint Biomarkers
Current Endpoints:
- Motor scores (MDS-UPDRS)
- Non-motor scales
- Quality of life measures
- NfL for progression
- Imaging for target engagement
- Alpha-synuclein for drug effect
Clinical Trial Design
Enrichment Strategies:
- Biomarker-positive patients
- Rapid progressors
- Genetic carriers
- N-of-1 approaches
- Basket trials
- Adaptive designs
Conclusion
PD biomarkers have advanced significantly but remain less established than AD biomarkers. Alpha-synuclein species in CSF and blood represent the most disease-specific markers, while neuroimaging and neurodegeneration markers provide complementary information. The integration of multiple biomarker categories enables more accurate diagnosis, prognosis, and clinical trial design. Continued development of accessible blood-based biomarkers and progression markers is a priority for PD research and clinical care.
See Also
- [Alpha-Synuclein Pathology](/mechanisms/alpha-synuclein)
- [Mitochondrial Dysfunction](/mechanisms/mitochondrial-dysfunction)
- [Neuroinflammation](/mechanisms/neuroinflammation-across-neurodegeneration)
- [Oxidative Stress](/mechanisms/oxidative-stress-neurodegeneration)
- [Protein Aggregation](/mechanisms/protein-aggregation)
- [Autophagy Dysfunction](/mechanisms/autophagy-lysosomal-pathways)
- [Neurodegeneration Overview](/mechanisms/neurodegeneration-overview)
- [Dopamine Signaling](/mechanisms/dopamine-signaling-pathway)
- [LRRK2 Pathway](/mechanisms/lrrk2-pathway)
- [GBA Pathway](/mechanisms/gba-glucocerebrosidase)
External Links
- [PubMed](https://pubmed.ncbi.nlm.nih.gov/)
- [KEGG Pathways](https://www.genome.jp/kegg/pathway.html)
References
Related Hypotheses
From the [SciDEX Exchange](/exchange) — scored by multi-agent debate
- [Multi-Modal Stress Response Harmonization](/hypothesis/h-1e564178) — <span style="color:#81c784;font-weight:600">0.68</span> · Target: NR3C1/CRH/TNFA
- [Circadian-Synchronized Proteostasis Enhancement](/hypothesis/h-0e0cc0c1) — <span style="color:#81c784;font-weight:600">0.67</span> · Target: CLOCK/ULK1
- [Digital Twin-Guided Metabolic Reprogramming](/hypothesis/h-b0cda336) — <span style="color:#81c784;font-weight:600">0.67</span> · Target: PPARGC1A/PRKAA1
- [Smartphone-Detected Motor Variability Correction](/hypothesis/h-072b2f5d) — <span style="color:#81c784;font-weight:600">0.63</span> · Target: DRD2/SNCA
- [Retinal Vascular Microcirculation Rescue](/hypothesis/h-35f04e1b) — <span style="color:#ffd54f;font-weight:600">0.55</span> · Target: PDGFRB/ANGPT1
- [Vocal Cord Neuroplasticity Stimulation](/hypothesis/h-e0183502) — <span style="color:#ffd54f;font-weight:600">0.48</span> · Target: CHR2/BDNF
- [Ocular Immune Privilege Extension](/hypothesis/h-6a065252) — <span style="color:#ffd54f;font-weight:600">0.43</span> · Target: FOXP3/TGFB1
Related Analyses:
- [Digital biomarkers and AI-driven early detection of neurodegeneration](/analysis/SDA-2026-04-01-gap-012) 🔄
- [Extracellular vesicle biomarkers for early AD detection](/analysis/SDA-2026-04-02-gap-ev-ad-biomarkers) 🔄
▸Metadataorigin_type: v1_polymorphic_backfill
| slug | mechanisms-biomarkers-parkinsons |
| kg_node_id | None |
| entity_type | mechanism |
| origin_type | v1_polymorphic_backfill |
| source_table | wiki_pages |
| wiki_page_id | wp-f4bbcec9da6b |
| __merged_from | {'merged_at': '2026-05-13', 'unprefixed_id': 'mechanisms-biomarkers-parkinsons'} |
| _schema_version | 1 |
No provenance edges found
Use ?embed=1 to load the artifact without SciDEX chrome — suitable for iframing into wiki pages or external sites.
<iframe src="http://scidex.ai/artifact/wiki-mechanisms-biomarkers-parkinsons?embed=1" width="100%" height="600" style="border:0;border-radius:8px"></iframe>
[Biomarkers for Parkinson's Disease](http://scidex.ai/artifact/wiki-mechanisms-biomarkers-parkinsons)
http://scidex.ai/artifact/wiki-mechanisms-biomarkers-parkinsons