Repeat expansion disorders are a group of inherited neuromuscular diseases, which are caused by expansion mutations of repeat sequences in the disease-causing genes. Repeat expansion disorders include a class of diseases caused by repeat expansions in the coding region of the genes, producing mutant proteins with amino acid repeats, mostly the polyglutamine (polyQ) diseases, and another class of diseases caused by repeat expansions in the noncoding regions, producing aberrant RNA with expanded repeats, which are called noncoding repeat expansion diseases. A variety of Drosophila disease models have been established for both types of diseases, and they have made significant contributions toward elucidating the molecular mechanisms of and developing therapies for these neuromuscular diseases.
Keywords: Amyotrophic lateral sclerosis; Drosophila; Neurodegenerative diseases; Noncoding repeat expansion diseases; Polyglutamine diseases; RNA foci; Repeat expansion diseases; Repeat-associated non-ATG translation; Spinocerebellar ataxia.