Article

Dopaminergic dysfunction in unrelated, asymptomatic carriers of a single parkin mutation.

MRC Clinical Sciences Centre, and Division of Neuroscience, Faculty of Medicine, Imperial College, Hammersmith Hospital, London, UK.
Neurology (Impact Factor: 8.3). 02/2005; 64(1):134-6. DOI: 10.1212/01.WNL.0000148725.48740.6D
Source: PubMed

ABSTRACT Parkin disease is usually autosomal recessive; however, two studies have shown that asymptomatic heterozygotes have nigrostriatal dysfunction and even manifest subtle extrapyramidal signs. The authors used 18F-dopa PET to study 13 asymptomatic parkin heterozygotes and found a significant reduction of (18)F-dopa uptake in caudate, putamen, ventral, and dorsal midbrain compared with control subjects. Four had subtle extrapyramidal signs. Parkin heterozygosity is a risk factor for nigrostriatal dysfunction and in some may contribute to late-onset Parkinson disease.

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