Developments in the molecular biology of DYT1 dystonia

The identification of a mutation of the DYT1 gene as a cause of inherited dystonia has led to many insights regarding the genetics of this disorder. In addition, there is a rapidly expanding list of inherited dystonia syndromes, the genes for some of which have been identified or localized. The DYT1 mutation has been found in a variety of ethnic groups, and it may result in a range of phenotypes. To date, studies of torsinA, the protein product of the DYT1 gene, have not revealed its function, although its widespread distribution throughout the central nervous system suggests a universal role. TorsinA has structural homology to heat shock and chaperone proteins. Evidence from studies in cell cultures and Caenorhabditis elegans , and the presence of torsinA in inclusion bodies in several neurodegenerative diseases may be indicative of a function of this nature. Preliminary studies in humans with DYT1 dystonia and in DYT1 transgenic mice suggest disruption of the dopaminergic nigrostriatal system. A functional interference with neuronal signal processing induced by mutation of torsinA is consistent with current hypotheses regarding impairment of the center‐surround mechanism in the striatum. © 2003 Movement Disorder Society