Autosomal dominant, fully penetrant, chromosome 4p16

1. extrapyramidal involuntary movements

2. abnormal ocular control

3.sleep disturbance- prolonged sleep onset latency, interspersed wakefulness

4. oral motor dysfunction in individuals at risk

5. first trimester prenatal diagnosis with DNA probes

1.atrophy of basal ganglia, especially caudate nuclei. The bicaudate ratio shows highest sensitivity and specifity in mildly affected individuals. This is also associated with atrophy of cerebellum, brainstem, and cerebral cortex (manifested by ventricular dilatation and enlargement of cerebral sulci).

2. PET scan shows hypometabolism of glucose preceeding tissue loss - indices of caudate metabolism correlate with patient\'s overall functional capacity and indices of putamen metabolism with motor function (chorea, oculomotor abnormalities)

3. SPECT - hypoperfusion of caudate nucleu