| description | Protein which, if defective, causes parkinsonism. Parkinsonism refers to disorders, both genetic and non-genetic, characterized by four primary parkinsonian symptoms: tremor, rigidity, postural instability and bradykinesia, resulting from the loss or dysfunction of dopamine- producing neurons in the substantia nigra. Lewy bodies, intraneuronal accumulations of aggregated proteins, may or may not be present in the brain of the patients |