Huntington's disease-like 2

Huntington's disease like-2 (HDL2) is an autosomal dominant disorder that clinically and pathologically closely resembles Huntington's disease (HD). Like HD, HDL2 is characterized by mid-life onset, abnormalities of voluntary and involuntary movement, psychiatric syndromes, and dementia, with a relentless progress to death. The disease is rare, and thus far has only been detected in individuals of African ancestry. Striatal and cortical atrophy is prominent, as are intranuclear protein aggregates. Some, but not all, affected individuals have acanthocytosis. HDL2 is caused by a CAG/CTG expansion mutation on chromosome 16q24.3, in an alternatively spliced exon of junctophilin-3. The mechanism of HDL2 pathogenesis is uncertain, but may involve the toxic properties of mutant transcripts containing expanded CUG repeats.