Genetic Characterization of Movement Disorders and Dementias

* INCLUSION CRITERIA For Patients: * Diagnosis of a movement disorder or dementia by a neurologist or other qualified professional and accompanied by sufficient clinical and/or laboratory evidence to support the diagnosis * Confirmation of a movement disorder or dementia by study investigators or a qualified clinician by physical examination and/or review of medical records * Ages 18 and above * Able to provide consent or, in the case of minors, or cognitive impairment, have a legally-authorized representative to provide consent * Able to understand and participate in study procedures or for those without consent capacity, able to participate in study procedures AND has a legally authorized representative that understands the study procedures and can consent on their behalf. For unaffected family members of patients: * Unaffected relative of a patient diagnosed with a movement disorder or dementia enrolled in this protocol. For these purposes, we define a family member as an individual for which there is a demonstrable relationship with the proband in the pedigree. This is a standard approach used in family-based studies. Furthermore, the related patient (defined as a family member diagnosed with the disease of interest) must be enrolled in the study. * Ages 18 and above * Able to provide consent * Able to understand and participate in study procedures For unrelated healthy control individuals: * Be in good general health * Have no known movement disorder or dementia, or family member with a movement disorder or dementia * Age 18 and above * Able to provide consent * Able to understand and participate in study procedures EXCLUSION CRITERIA For patients: -An identifiable, non-genetic etiology for the movement disorder or dementia, such as a specific environmental exposure, birth injury, metabolic disorder, or brain infection such as encephalitis For all participants: * Clinically significant anemia that would make phlebotomy unsafe, and participant unwilling to provide saliva sample. * Clinically significant bleeding that would make phlebotomy unsafe, and participant unwilling to provide saliva sample. * Any medical condition that would make phlebotomy unsafe or undesirable, such as a serious medical illness like unstable heart disease, or unstable chronic obstructive pulmonary disease, and participant unwilling to provide saliva sample.