title: Homozygous THAP1 mutations as cause of early-onset generalized dystonia.
abstract: To identify the underlying genetic cause in a consanguineous family with apparently recessively inherited dystonia, we performed genome-wide homozygosity mapping. This revealed 2 candidate regions including the THAP1 gene, where heterozygous mutations cause dystonia 6. A homozygous missense mutation in THAP1 (c.95T>A; p.Leu32His) was found in all 3 affected siblings. Symptoms started in childhood in the legs and became generalized within a few years. Three heterozygous mutation carriers were unaffected. Because THAP1 regulates the expression of the DYT1 gene, we used reporter gene assays to show that DYT1 expression was significantly increased for Leu32His. However, this increase was less pronounced than for other THAP1 mutations that cause dystonia in the heterozygous state. Our data suggest that homozygous THAP1 mutations cause dystonia and may be associated with a less severe dysfunction of the encoded protein compared with heterozygous disease-causing mutations.
authors.affiliation: Section of Clinical and Molecular Neurogenetics at the Department of Neurology, University of Lübeck, Lübeck, Germany.
authors.forename: Susanne A
authors.initials: SA
authors.lastname: Schneider
authors.forename: Alfredo
authors.initials: A
authors.lastname: Ramirez
authors.forename: Kaveh
authors.initials: K
authors.lastname: Shafiee
authors.forename: Frank J
authors.initials: FJ
authors.lastname: Kaiser
authors.forename: Alev
authors.initials: A
authors.lastname: Erogullari
authors.forename: Norbert
authors.initials: N
authors.lastname: Brüggemann
authors.forename: Susen
authors.initials: S
authors.lastname: Winkler
authors.forename: Ideh
authors.initials: I
authors.lastname: Bahman
authors.forename: Alma
authors.initials: A
authors.lastname: Osmanovic
authors.forename: Mohammad A
authors.initials: MA
authors.lastname: Shafa
authors.forename: Kailish P
authors.initials: KP
authors.lastname: Bhatia
authors.forename: Hossein
authors.initials: H
authors.lastname: Najmabadi
authors.forename: Christine
authors.initials: C
authors.lastname: Klein
authors.forename: Katja
authors.initials: K
authors.lastname: Lohmann
mesh_terms: D000328:Adult; D051017:Apoptosis Regulatory Proteins / Q000235:genetics*; D002277:Carcinoma / Q000473:pathology; D045744:Cell Line, Tumor; D003241:Consanguinity; D004268:DNA-Binding Proteins / Q000235:genetics*; D004421:Dystonia / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D055106:Genome-Wide Association Study; D006639:Histidine / Q000235:genetics; D006720:Homozygote; D006801:Humans; D007492:Iran; D007930:Leucine / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009154:Mutation / Q000235:genetics*; D009687:Nuclear Proteins / Q000235:genetics*; D010375:Pedigree
chemical_list: D051017:Apoptosis Regulatory Proteins; D004268:DNA-Binding Proteins; D009687:Nuclear Proteins; C474080:THAP1 protein, human; D006639:Histidine; D007930:Leucine