parkin mutation dosage and the phenomenon of anticipation: a molecular genetic study of familial parkinsonism

Background parkin mutations are a common cause of parkinsonism. Possessing two parkin mutations leads to early-onset parkinsonism, while having one mutation may predispose to late-onset disease. This dosage pattern suggests that some parkin families should exhibit intergenerational variation in age at onset resembling anticipation. A subset of familial PD exhibits anticipation, the cause of which is unknown. The aim of this study was to determine if anticipation was due to parkin mutation dosage.