Cohort Study to Identify Predictor Factors of Onset and Progression of Parkinson's Disease

Inclusion Criteria: * All subjects: Male or female age 18 years and older, MMSE score \> 26, negative pregnancy test in potentially child-bearing women (contraindication to SPECT with DatScan). * Idiopathic Parkinson disease subjects: diagnosis confirmed according to UK Parkinson's Disease Society Brain Bank criteria (UKPDSBB); disease duration less than 3 years. * Genetic Parkinson disease subjects: parkinson diagnosis confirmed and mutation in parkin, LRRK2, SNCA or GBA genes. * Prodromal subjects: subjects with identified relative with PD genetically confirmed or subjects with diagnosis of idiopathic Rem sleep Behavior Disorder (iRBD); neurological examination normal (no signs of parkinsonism). * Healthy subjects: neurological examination normal Exclusion Criteria: * All subjects: Psychiatric disorder or any progressive life-threatening disease, impairment precluding appropriate information and instructions given concerning participation to the study; contra-indication to MRI or SPECT scan. * Parkinson disease subjects: no dopamine transporter deficit at SPECT scan; parkinsonism induced by neuroleptics; neuroleptics intake within 6 months; atypical parkinson syndrom (MSA, PSP, CBD...) * Parkinson disease subjects with mutation in Parkin, LRRK2, SNCA or GBA gene: atypical parkinson disease syndromes due to either drugs (e.g., metoclopramide, flunarizine, neuroleptics) or metabolic disorders (e.g., Wilson's disease), encephalitis or degenerative diseases (e.g., progressive supranuclear palsy) or currently taking neuroleptics or has taken neuroleptics within 6 months of baseline or any biological anomaly.