Huntington's chorea in the Cape coloured community of South Africa.

Huntington's chorea is a grave genetic neurological disorder which appears to be a more serious problem in South Africa than has generally been recognized. The minimum prevalence of the disease in the Cape Coloured is 3,5/100 000 of the population. Sixteen per cent of patients were younger than 20 years at the time of onset of the disease. This is among the highest incidence of juvenile Huntington's chorea in the world. The gene for Huntington's chorea has been in South Africa for 300 years. It was first introduced into this country from Holland in the middle of the 17th century and then later from England in the middle and end of the 19th century. The number of affected individuals appears to be on the increase in South Africa. Unfortunately, at present, no methods are available for effective control of this disorder.