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A Simple Composite Phenotype Scoring System for Evaluating Mouse Models of Cerebellar Ataxia
Published on: May 21, 2010
Autosomal dominant cerebellar ataxias
C Marelli1, C Cazeneuve, A Brice
1Département de génétique et cytogénétique, consultation de génétique clinique, CHU Pitié-Salpêtrière, AP-HP, 47, boulevard de l'Hôpital, 75013 Paris, France.
Revue Neurologique
|May 7, 2011
Summary
Autosomal dominant cerebellar ataxias (ADCA) are rare genetic disorders. This review details their genetic heterogeneity, identifying 20 genes and discussing how repeat expansions influence disease progression and clinical presentation.
Area of Science:
- Neurogenetics
- Neurology
- Molecular Biology
Background:
- Autosomal dominant cerebellar ataxias (ADCA) are rare compared to sporadic forms.
- Genetic heterogeneity is confirmed by identified genes, revealing diverse mechanisms and pathways.
- Phenotypes often extend beyond cerebellar dysfunction to multisystemic neurological deficits.
Purpose of the Study:
- To review the genetic features of ADCA.
- To discuss the clinical differences among various ADCA forms.
- To highlight the role of genetic heterogeneity in ADCA.
Main Methods:
- Literature review of genetic loci and genes associated with ADCA.
- Analysis of phenotype-genotype correlations, particularly repeat expansion sizes.
- Examination of mutation types (repeat expansions, conventional mutations, rearrangements).
Main Results:
- At least 28 genetic loci and 20 genes identified for ADCA.
- Seven specific ADCA (SCA1, 2, 3, 6, 7, 17, DRPLA) are caused by repeat expansions.
- Repeat size correlates with disease progression, severity, and anticipation across generations.
Conclusions:
- ADCA genetics are diverse, involving various genes and mutation types.
- Repeat expansions are a common mechanism, influencing disease characteristics.
- Understanding genetic features is crucial for differentiating ADCA forms and their clinical outcomes.
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