Juvenile Huntington Disease
Individuals with juvenile Huntington disease usually inherit the disease from their fathers. The reason for this may be found in the process of sperm production. Unlike eggs, sperm are produced in the millions. Because DNA is copied millions of times during this process, there is an increased possibility for genetic mistakes to occur.
(Click Inheriting Huntington's Disease to learn how someone inherits the Huntington disease gene mutation.)
A common symptom of juvenile Huntington disease is a rapid decline in school performance. Juvenile Huntington disease symptoms can also include subtle changes in handwriting and slight problems with movement (such as slowness, rigidity, tremor, and rapid muscular twitching) called myoclonus. Several of these symptoms are similar to those seen in Parkinson's disease, and they differ from the chorea seen in individuals who develop HD as adults. These young individuals are said to have "akinetic-rigid" Huntington disease or the Westphal variant of Huntington disease.
People with juvenile Huntington disease may also have seizures and mental disabilities.
A diagnosis of juvenile Huntington disease can be made by experienced neurologists. In order to diagnose juvenile Huntington disease, the doctor will usually ask a number of questions about the patient's personal and family medical history, perform a physical exam, and recommend certain tests.
(Click Diagnosing Huntington's Disease for more information. To learn more about genetic testing for HD, see the eMedTV article Huntington's Disease Genetic Testing.)