Myopathy with extrapyramidal signs is an autosomal recessive disorder characterized by early childhood onset of proximal muscle weakness and learning disabilities. While the muscle weakness is static, most patients develop progressive extrapyramidal signs that may become disabling (summary by Logan et al., 2014). Brain MRI in 1 patient showed congenital malformations, including polymicrogyria and cerebellar dysplasia (Wilton et al., 2020).