The genetic complexity and heterogeneity of the sporadic forms of Parkinson's disease (PD) are posing a formidable challenge to disentangle their direct molecular causes. To advance this research, we plan to coordinate our local biorepositories of PD biological specimens creating a standardized and integrated national resource. In this framework, we plan to collect more samples from additional sporadic PD cases and to extend the sampling to patients with REM sleep behavior disease. We plan a large campaign of whole genome sequencing including about 200 patients to identify rare genomic variants plausibly associated with these diseases. In addition, we will standardize the generation and quality control of iPSC lines to make available to the scientific community. Finally, we will combine iPSC technology and gene editing to functionally assess the relative impact of rare variants in coding regions inherited together as a polygenic trait previously identified in selected sporadic PD cases

The project is a multicentric observational study. Instuitutions involved are:

IRCCS Hospital San Raffaele, Milan Italy (coordinator Operating Unit (OU1)) IRCCS INM Neuromed, Pozzilli, (IS) Italy (Operating Unit (OU2)) IRCCS San Raffaele Roma, (Operating Unit (OU3)) The project takes advantage from the availability of a large collection of PD samples (~800) PD from familiar and sporadic cases, recruited at IRCCS Neuromed, for which we already collected and stored clinical information, genetic data as well as DNA, serum, plasma and peripheral blood mononuclear cells (PBMCs) for the entire study cohort.

The activities of the IRCCS INM Neuromed are:

1. standardization of the clinical reporting, sample collection, storage and identification between the centers;
2. recruitment of 100 PD patients, 30 RBD patients and 100 healthy subjects (patients' wives/husbands), to be carried out during the scheduled outpatient visits for these patients;
3. whole genome sequencing (WGS) and bioinformatic analysis (in collaboration with OU1) of a selected cohort of PD patients (200 samples), negative for mutations/variants in PD candidate genes;
4. WGS analysis of REM sleep behaviour disorder (RBD) prodromal patients as a model to identify early biomarker for PD;
5. development of an innovative protocol for early diagnosis of PD based on the co-inheritance of multiple rare deleterious variants in PD genes;
6. generation of induced pluripotent cell lines (iPSC) by reprogramming PBMCs from PD patients and familiar healthy donors.

After signed informed consent patients will be assessed for disease progression (Stadio di Hoehn and Yahr, MDS-UPDRS part III, MOCA test, no motor symptoms, therapy and LID occurrence, sleep behavior disease). Each patient and control will be subjected to peripheral blood sampling for the isolation of DNA, plasma, serum, PBMC. For a subset of patients induced pluripotent stem cells (iPSC) will be generated starting from PBMC.

Whole genome sequencing approach will be used to identify novel associated vatiants.

Extensive computational analysis will be planned to map the SNPs to regulatory regions controlling the expression of selected genes. This effort will provide the initial knowledge to draft the association between particular genomic SNPs and their combinations with sporadic PD. This endeavor is critical to advance our understanding of the genetic roots of PD and is in line with analogous ongoing international studies with whom will seek coordination. The success of this research will provide the means for developing predictive genetic testing and counselling of patients with PD and their families.

To increase the power analysis data will be analyzed including WES data of a cohort of 800 PD patients and 300 healthy subject already available at IRCCS INM Neuromed.

Inclusion Criteria PD patients:

• Presence of at least 2 of the 4 cardinal signs (tremor, rigidity, bradykinesia, onset asymmetric) one of which must be tremor or bradykinesia;
• Absence of atypical symptoms such as: i) early postural instability, freezing phenomena, cognitive impairment, hallucinations, pathological involuntary movements, vertical gaze paralysis; ii) confirmed causes of secondary parkinsonism (focal lesions, drugs, substances toxic);
• Documented response to L-dopa or dopamine agonist use (or lack of adequate therapeutic attempt with L-dopa or dopamine agonists).

Inclusion Criteria RBD patients:

• Subjects affected by idiopathic RBD that will be selected according to the most recent criteria international classification of sleep disorders (ICSD-3).

Exclusion Criteria:

• pre-existing psychiatric conditions;
• Neurodegenerative neurological diseases such as multiple sclerosis, lateral sclerosis amyotrophic, Alzheimer's, neuromuscular pathologies, epilepsy;
• diagnosis of dementia;
• depression;
• prolonged intake of anxiolytics, antidepressants, antipsychotics, hypnotic drugs, cognitive stimulants

The study includes 100 PD patients, 30 RBD and 100 age/gender-matched controls. All PD patients will be diagnosed at the IRCCS Neuromed and followed-up (at least for 3 years) for disease progression

genetic data