Positron Emission Tomography (PET) Imaging in People With Gaucher Mutations

This study will use positron emission tomography (PET) to compare how people with Gaucher disease or Gaucher disease carriers with parkinsonism, and their family members, use dopamine in their brains in comparison with healthy normal volunteers and people who have Parkinson disease. PET assesses organ function by measuring metabolism. In this study, magnetic resonance imaging (MRI) is used in conjunction with PET to help better interpret and understand the information gleaned from PET. People 21 years of age and older with the following conditions may be eligible for this study: * Gaucher disease and parkinsonism * Parkinsonism and a family history of Gaucher disease * Gaucher disease and a family history of parkinsonism * Gaucher disease carriers who have parkinsonism or a family history of parkinsonism * Unaffected people with a family history of Gaucher disease and parkinsonism * Healthy volunteers Participants undergo the following tests and procedures: * Personal and family medical history * Physical examination * PET scan: The subject lies on a table that slides into the PET scanner until his or her head is positioned properly in the scanner. A catheter is inserted into a vein. An initial scan is done to obtain images before radionuclides are injected. Radioactive water is then injected through the catheter and the subject is asked questions in order to stimulate blood flow in certain areas of the brain to show what parts of the brain are activated. Fluorodopa is then infused through the catheter over 3 minutes. The PET scan can last up to 2 hours. * MRI scan: This test uses a magnetic field and radio waves to obtain images of organs. The subject lies still on a bed in the middle of a circular scanner for about 30 minutes.