• CAG repeat;
  • dentatorubral-pallidoluysian atrophy;
  • polyglutamine

Dentatorubral-pallidoluysian atrophy (DRPLA) is a hereditary spinocerebellar degeneration. Despite the establishment of this disease in 1982, it has been pointed out that DRPLA has an unexplained aspect concerning its clinicopathological features; that is, the discrepancy between the variety of clinical manifestations and the uniformity of the brain lesions. The discovery of a causative gene mutation (abnormal expansion of the CAG repeat in DRPLA gene) triggered the development of novel neuropathology in DRPLA, which has suggested that polyglutamine-related pathogenesis involves a wide range of central nervous system regions far beyond the systems previously reported to be affected. It is now likely that DRPLA has an aspect of neuronal storage disorder and has multiple system degeneration, the lesion distribution of which varies depending on the CAG repeat sizes in the causative gene.