Cathepsin D deficiency causes juvenile-onset ataxia and distinctive muscle pathology

The neuronal ceroid lipofuscinoses (NCLs) are a heterogeneous group of neurodegenerative disorders with the most common phenotype consisting of early-onset progressive motor deterioration, cognitive decline, visual failure, epilepsy, cerebellar ataxia, and premature death.1 Acknowledgment: The authors thank the patients and families for help and support.