A rare genetic neurological disorder characterised by paediatric onset of calcifying leucoencephalopathy and skeletal dysplasia. Reported structural brain abnormalities include agenesis of corpus callosum, ventriculomegaly, congenital hydrocephalus, pontocerebellar hypoplasia, periventricular calcifications, Dandy-Walker malformation and absence of microglia. Characteristic skeletal features include increased bone mineral density (reported in skull, pelvic bone and vertebrae), platyspondyly, and under-modelling of tubular bones with widened/radiolucent metaphysis and constricted/sclerotic diaphysis. [from SNOMEDCT_US]