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S Perman

Publications and source records attributed to S Perman.

4 recordsLinked to original sources

Torsion dystonia genes in two populations confined to a small region on chromosome 9q32-34.

Idiopathic torsion dystonia (ITD) is characterized by sustained, involuntary muscle contractions, frequently causing twisting and repetitive movements or abnormal postures. Most familial forms of ITD display autosomal dominant inheritance with reduced penetrance. Linkage analysis has been previously used to localize a dystonia gene to the 9q32-34 region in a large non-Jewish family and in a group of Ashkenazi Jewish families. Utilizing GT repeat polymorphisms from this region, here we demonstrate that the gene causing dystonia in Ashkenazi Jews can be localized to the 11-cM interval between AK1 and D9S10. Linkage analysis in the non-Jewish family is also consistent with occurrence of the gene in this region, although positive lod scores extend over a greater than 20-cM interval in that family. These results set the stage for positional cloning of the dystonia gene. Currently there are no known candidate genes in this region.

Base Sequence↗

Identification of a highly polymorphic microsatellite VNTR within the argininosuccinate synthetase locus: exclusion of the dystonia gene on 9q32-34 as the cause of dopa-responsive dystonia in a large kindred.

Dopa-responsive dystonia is a clinical variant of idiopathic torsion dystonia that is distinguished from other forms of dystonia by the frequent occurrence of parkinsonism, diurnal fluctuation of symptoms, and its dramatic therapeutic response to L-dopa. Linkage of a gene causing classic dystonia in a large non-Jewish kindred (DYT1) and in a group of Ashkenazi Jewish families, to the gelsolin (GSN) and arginino-succinate synthetase (ASS) loci on chromosome 9q32-34, respectively, was recently determined. Here we report the discovery of a highly informative (GT)n repeat VNTR polymorphism within the ASS locus. Analysis of a large kindred with dopa-responsive dystonia, using this new polymorphism and conventional RFLPs for the 9q32-34 region, excludes loci in this region as a cause of this form of dystonia. This provides proof of genetic heterogeneity between classic idiopathic torsion dystonia and dopa-responsive dystonia.

Argininosuccinate Synthase↗