Model Systems for Spinocerebellar Ataxias: Lessons Learned About the Pathogenesis

Model systems are important tools for the investigation of pathogenic processes. Especially for diseases with a late onset of symptoms and slow progression, like most spinocerebellar ataxias (SCA), it is time-consuming or even impossible to analyze all aspects of the pathogenesis in humans. Due to the reduced lifespan of model organisms, it is possible to study disease progression in full within a reasonable timeframe and due to the shorter generation time of most model organisms more individuals can be generated and analyzed, thereby strengthening the reliability of data via an increased number of replicates. Detailed studies of the histopathology can only be performed as endpoint analyses in humans, but with the help of an animal model, multiple time points can be analyzed throughout the course of the disease. In addition, model systems allow not only for the reduction of time from idea to results but also reduce the complexity due to their smaller genome sizes, less genes, nonredundant pathways, and a simpler nervous system.