[Perspective] One target for amyotrophic lateral sclerosis therapy?
Repeat expansion mutations cause a range of developmental, neurodegenerative, and neuromuscular disorders. The repeat sequences generally comprise a 3– to 6–base pair repeat unit that expands above a critical threshold, leading to disease. Expanded repeats cause disease via a range of mechanisms, including loss of function of the repeat-containing protein and production of toxic repeat RNAs and proteins, making the disorders difficult to treat. In 2011, a hexanucleotide repeat expansion in the C9orf72 gene was identified as the most common cause of frontotemporal dementia and amyotrophic lateral sclerosis (termed c9FTD/ALS) (1, 2). On page 708 of this issue, Kramer et al. (3) report that targeting a single factor, Spt4, reduced production of C9orf72 repeat expansion–associated RNA and protein, and ameliorated neurodegeneration in model systems. Authors: Sarah Mizielinska, Adrian M. Isaacs