Genetic diagnosis of hyperkinetic movement disorders

People with hyperkinetic movements have always attracted the attention of the public and professionals. Alert colleagues noticed families in which a disease passed from generation to generation around Lake Maracaibo in Venezuela. This study led in 1993 to the localization of the gene for Huntington disease on chromosome 4. The genetic basis of many other familial and sporadic diseases has been identified on human DNA.

The clinical presentation of hyperkinesias remains the starting point for diagnosis, but differential diagnosis is a long, difficult process, the first step being to differentiate between inherited and non-inherited forms. The need to know the diagnosis is of major importance for patient and family. Knowledge about the cause limits the number of extra diagnostics. This review of the literature presents the most frequently occurring genetically-determined forms of hyperkinesias, mainly chorea and dystonia and tries to give some practical guidelines.

The final part of the review will offer some thoughts and views for future development in a world which probably has more knowledge than we can handle. The drive to find a diagnosis is rewarded by the patient but one also needs to reflect on the use of medical care.