The study population will include 100 parkinsonian patients in early stage of disease, with total duration not exeeding 5 years.

The patients will undergo neurologic examination and evaluation of disease severity using the unified PD rating scale. Subsequently a brain SPECT will be performed using Tc-99m-Trodat1.

The study sample will include 100 Israeli Jewish patients with early idiopathic PD who were not treated with anti-parkinson drugs. The clinical diagnosis will be based on the criteria of the United Kingdom Parkinson Disease Society Brain Bank.5 All patients will undergo Tc-99m-Trodat1 SPECT. The severity of the motor symptoms will be assessed with the Unified PD Rating Scale (UPDRS). Genomic DNA is extracted from peripheral blood leukocytes for genetic analysis.

Inclusion Criteria:

Inclusion criteria were

1. early Israeli PD patients
2. Of jewish origin, males or females
3. Undergoing DAT-scan examination in Wolfson medical center at early stage of disease, accompanied by a UPDRS evaluation at that stage,performed by a trained neurologist
4. Patients did not use any type of anti-parkinsonian drug type, at time of DAT-scan performance and UPDRS evaluation
5. DNA sample was obtained
6. Patients were able to sign an informed consent form to participate in this study.

Exclusion Criteria:

• Patients were excluded if they features secondary parkinsonism or if they were treated with medications that block dopamine receptors.

100 early Israeli PD patients Of jewish origin, males or females Undergoing DAT-scan examination in Wolfson medical center at early stage of disease, accompanied by a UPDRS evaluation at that stage,performed by a trained neurologist