Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027066 (myoclonus)
 4,275 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary autosomal dominant myoclonus dystonia (MD) is a movement disorder characterized by involuntary lightning jerks and dystonic movements and postures alleviated by alcohol. Although various large families with MD have been described, no positive linkage has been found to a chromosomal location. We report a family with eight members with MD. Linkage analysis identified a 23-centimorgan region on chromosome 11q23 that cosegregates with the disease state (maximum multipoint logarithm of odds score = 2.96 at D11S897). This region contains an excellent candidate gene for involvement in the etiology of MD, the D2 dopamine receptor (DRD2) gene. Neurotransmission mediated by DRD2 is known to have a key role in the control of movement and also has been implicated in reward and reinforcement mechanisms and psychiatric disorders. Sequencing of the coding region of DRD2 indicated that all affected and obligate carriers were heterozygous for a Val154Ile change in exon 3 of the protein, which is highly conserved across species. This change was found neither in other unaffected members of the pedigree nor in 250 control chromosomes. Our finding provides evidence for the involvement of DRD2 in a disorder of the central nervous system and should lead to further insight into the function of the dopaminergic system in dystonia and other movement and mood disorders.
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PMID:Association of a missense change in the D2 dopamine receptor with myoclonus dystonia. 1022 Apr 38

A novel Val154-->Ile mutation in the D2 dopamine receptor (DRD2) on chromosome 11q23 has recently been shown to be associated with myoclonus dystonia (M-D) in one large family. Sequence analysis of the DRD2 gene in 5 M-D patients from different families did not reveal any mutations, nor was there evidence of linkage to the 11q23 region in the DRD2 gene in four other families. Receptor binding and signal transduction assays of the DRD2 mutant and wild-type receptors revealed identical agonist and antagonist affinities and functional responses. These studies suggest that M-D is genetically heterogeneous. The molecular mechanisms through which the Val-->Ile mutation may contribute to M-D remain to be determined.
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PMID:Evaluation of the role of the D2 dopamine receptor in myoclonus dystonia. 1071 58

Myoclonus-dystonia (M-D) is an autosomal dominant disorder characterized by myoclonic and dystonic muscle contractions that are often responsive to alcohol. The dopamine D2 receptor gene (DRD2) on chromosome 11q has been implicated in one family with this syndrome, and linkage to a 28-cM region on 7q has been reported in another. We performed genetic studies, using eight additional families with M-D, to assess these two loci. No evidence for linkage was found for 11q markers. However, all eight of these families showed linkage to chromosome 7 markers, with a combined multipoint LOD score of 11.71. Recombination events in the families define the disease gene within a 14-cM interval flanked by D7S2212 and D7S821. These data provide evidence for a major locus for M-D on chromosome 7q21.
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PMID:A major locus for myoclonus-dystonia maps to chromosome 7q in eight families. 1102 10

Myoclonus-dystonia is a movement disorder associated with mutations in the epsilon-sarcoglycan gene (SGCE) in most families and in the DRD2 and DYT1 genes in two single families. In both of the latter families, we also found a mutation of SGCE. The molecular mechanisms through which the detected mutations may contribute to myoclonus-dystonia remain to be determined.
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PMID:Epsilon-sarcoglycan mutations found in combination with other dystonia gene mutations. 1240 71

Myoclonus-dystonia (M-D) is an autosomal-dominant movement disorder with onset in the first two decades of life. Mutations in the epsilon-sarcoglycan gene (SGCE, DYT11) on chromosome 7q21-q31 represent the major genetic cause of M-D in some populations. The syndrome was related with mutations in two other genes (DRD2 and DYT1). A second locus has been reported in one large M-D family (DYT15, 18p11), but no gene has been identified yet. In this review, we discuss genetic aspects of myoclonus-dystonia.
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PMID:Genetic Aspects of Myoclonus-Dystonia Syndrome (MDS). 2679 Jun 71