Huntington's disease-like 2 in Brazil--report of 4 patients.

Huntington's disease-like 2 (HDL2) is a neurodegenerative disorder found in people of African ancestry with clinical, radiological, and neuropathological manifestations similar to Huntington's disease (HD). HDL2 is caused by a pathological expansion of CAG/CTG triplets in exon 2A of the JPH3 gene. We describe four cases of HDL2 from four unrelated families, and discuss their clinical findings. HDL2 should be considered in every patient with an HD-like phenotype who tests negative for the HD mutation, even if African ancestry is not immediately apparent.