A DUTCH FAMILY WITH BENIGN HEREDITARY CHOREA OF EARLY-ONSET - DIFFERENTIATION FROM HUNTINGTONS-DISEASE

A large Dutch family of 88 members, running through five generations, is described with benign hereditary chorea of early onset. The clinica l presentation was heterogeneous. The chorea manifested in late infanc y or childhood, interfered with writing, was non-disabling, stable or even improved in adulthood in most cases, but was slowly progressive w ith gait impairment in some. There was mild dysarthria and normal inte lligence. EEG, brain CT-scanning and MRI were normal. Huntington's dis ease was excluded by analysis of the I T 15 gene, which showed a norma l number of the CAG trinucleotide repeats in two patients. It is concl uded that benign hereditary chorea of early onset is an entity differe nt from Huntington's disease and that in cases of early onset chorea t he diagnostic accuracy is markedly improved by DNA testing.