_:vb50940707 . _:vb50940707 "url:https://pubmed.ncbi.nlm.nih.gov/28931644/"^^ . _:vb50940707 "A hypomyelinating leukodystrophy that is characterized by hypotonia, almost complete lack of motor or cognitive skills, and absent language development and that has_material_basis_in homozygous mutation in the UFM1 gene on chromosome 13q13."^^ . _:vb50940707 . _:vb50940707 . _:vb50940707 .