A significant minority of cases of Huntington's disease commence before the age of 20 years and these juvenile cases are more likely to demonstrate paternal transmission and a clinical picture dominated by rigidity. Genetic research and positron emission tomography may make early diagnosis easier but predictive testing in childhood is replete with serious problems. There is no specific treatment for this fatal disorder. Juvenile Huntington's disease has a similar pathology and biochemistry to the adult condition despite a shorter course and certain clinical differences, such as rigidity and convulsions. Racial differences are explored.
