Polyglutamine-expanded ataxin-3: a target engagement marker for Spinocerebellar ataxia type 3 in peripheral blood

Abstract Spinocerebellar ataxia type 3 is a rare neurodegenerative disease, caused by a CAG repeat expansion leading to polyglutamine elongation in the ataxin-3 protein. While no curative therapy is yet available, preclinical gene silencing approaches to reduce polyglutamine-toxicity demonstrate promising results. In view of upcoming clinical trials, quantitative and easily accessible molecular markers are of critical importance as pharmacodynamic and particularly as target engagement markers. We developed a novel ultrasensitive immunoassay to measure specifically polyQ-expanded ataxin-3 in plasma and cerebrospinal fluid. Statistical analyses revealed a correlation with clinical parameters and a stability of polyglutamine-expanded ataxin-3 during conversion from the pre-ataxic to the ataxic phase.

Download Full-text

Somatic mosaicism of the CAG repeat expansion in spinocerebellar ataxia type 3/Machado-Joseph disease

Human Mutation ◽

10.1002/(sici)1098-1004(1998)11:1<23::aid-humu4>3.0.co;2-m ◽

1998 ◽

Vol 11 (1) ◽

pp. 23-27 ◽

Cited By ~ 29

Author(s):

Géraldine Cancel ◽

Isabelle Gourfinkel-An ◽

Giovanni Stevanin ◽

Olivier Didierjean ◽

Nacer Abbas ◽

...

Keyword(s):

Spinocerebellar Ataxia ◽

Somatic Mosaicism ◽

Repeat Expansion ◽

Cag Repeat ◽

Spinocerebellar Ataxia Type ◽

Spinocerebellar Ataxia Type 3 ◽

Cag Repeat Expansion ◽

Machado Joseph Disease ◽

Type 3

Download Full-text

Polyglutamine‐Expanded Ataxin‐3: A Target Engagement Marker for Spinocerebellar Ataxia Type 3 in Peripheral Blood

Movement Disorders ◽

10.1002/mds.28749 ◽

2021 ◽

Author(s):

Jeannette Hübener‐Schmid ◽

Kirsten Kuhlbrodt ◽

Julien Peladan ◽

Jennifer Faber ◽

Magda M. Santana ◽

...

Keyword(s):

Spinocerebellar Ataxia ◽

Peripheral Blood ◽

Spinocerebellar Ataxia Type ◽

Target Engagement ◽

Spinocerebellar Ataxia Type 3 ◽

Type 3

Download Full-text

Homozygous spinocerebellar ataxia type 3 in China: a case report

Journal of International Medical Research ◽

10.1177/03000605211021370 ◽

2021 ◽

Vol 49 (6) ◽

pp. 030006052110213

Author(s):

Yuchao Chen ◽

Dan Li ◽

Minger Wei ◽

Menglu Zhou ◽

Linan Zhang ◽

...

Keyword(s):

Spinocerebellar Ataxia ◽

Clinical Phenotype ◽

Gene Dosage ◽

Cag Repeat ◽

Cag Repeats ◽

Spinocerebellar Ataxia Type ◽

Contraction Pattern ◽

Spinocerebellar Ataxia Type 3 ◽

Type 3 ◽

Stable Transmission

Spinocerebellar ataxia type 3 (SCA3) is a neurodegenerative disease caused by a heterozygous CAG repeat expansion in the ataxin 3 gene ( ATXN3). However, patients with homozygous SCA3 carrying expanded CAG repeats in both alleles of ATXN3 are extremely rare. Herein, we present a case of a 50-year-old female who had homozygous SCA3 with expansion of 62/62 repeats. Segregation analysis of the patient’s family showed both a contraction pattern of CAG repeat length and stable transmission. The present case demonstrated an earlier onset and more severe clinical phenotype than that seen in heterozygous individuals, suggesting that the gene dosage enhances disease severity.

Download Full-text

Dystonia in Patients with Spinocerebellar Ataxia 3 - Machado-Joseph disease: An Underestimated Diagnosis?

The Open Neurology Journal ◽

10.2174/1874205x01812010041 ◽

2018 ◽

Vol 12 (1) ◽

pp. 41-49 ◽

Cited By ~ 2

Author(s):

Ligia Maria Perrucci Catai ◽

Carlos Henrique Ferreira Camargo ◽

Adriana Moro ◽

Gustavo Ribas ◽

Salmo Raskin ◽

...

Keyword(s):

Spinocerebellar Ataxia ◽

Movement Disorders ◽

Disease Onset ◽

Cag Repeat ◽

Spinocerebellar Ataxia Type ◽

Spinocerebellar Ataxia Type 3 ◽

Generalized Dystonia ◽

Machado Joseph Disease ◽

Sca3 Patient ◽

Type 3

Background:Spinocerebellar Ataxia type 3 (SCA3) or Machado-Joseph Disease (MJD) is characterized by cerebellar, central and peripheral symptoms, including movement disorders. Dystonia can be classified as hereditary and neurodegenerative when present in SCA3.Objective:The objective of this study was to evaluate the dystonia characteristics in patients with MJD.Method:We identified all SCA3 patients with dystonia from the SCA3 HC-UFPR database, between December 2015 and December 2016.Their medical records were reviewed to verify the diagnosis of dystonia and obtain demographic and clinical data. Standardized evaluation was carried out through the classification of Movement Disorders Society of 2013 and Burke Fahn-Marsden scale (BFM).Results:Amongst the presenting some common characteristics, 381 patients with SCA3, 14 (3.7%) subjects presented dystonia: 5 blepharospasm, 1 cervical dystonia, 3 oromandibular, 3 multifocal and 2 generalized dystonia. Regarding dystonia's subtypes, 71.4% had SCA3 subtype I and 28.6% SCA3 subtype II. The average age of the disease onset was 40±10.7 years; the SCA3 disease duration was 11.86± 6.13 years; the CAG repeat lengths ranged from 75 to 78, and the BFM scores ranged from 1.0 to 40. There was no correlation between the dystonia severity and CAG repeat lengths or the SCA3 clinical evolution.Conclusion:Dystonia in SCA3 is frequent and displays highly variable clinical profiles and severity grades. Dystonia is therefore a present symptom in SCA3, which may precede the SCA3 classic symptoms. Dystonia diagnosis is yet to be properly recognized within SCA3 patient.

Download Full-text