has material basis in germline mutation in B4GALNT1 hereditary spastic paraplegia 26 https://github.com/monarch-initiative/mondo/issues/6878 https://www.malacards.org/card/spastic_paraplegia_26_autosomal_recessive spastic paraplegia 26 MEDGEN:373138 OMIM:609195 DOID:0110777 autosomal recessive spastic paraplegia type 26 spastic paraplegia 26, autosomal recessive MONDO:0012213 GM2 synthase deficiency SCTID:726607007 MESH:C536862 hereditary spastic paraplegia type 26 UMLS:C1836632 Orphanet:101006 GARD:0009587 A rare, complex type of hereditary spastic paraplegia characterized by the onset in childhood/adolescence (ages 2-19) of progressive spastic paraplegia associated mainly with mild to moderate cognitive impairment and developmental delay, cerebellar ataxia, dysarthria, and peripheral neuropathy. Less commonly reported manifestations include skeletal abnormalities (i.e. pes cavus, scoliosis), dyskinesia, dystonia, cataracts, cerebellar signs (i.e. saccadic dysfunction, nystagmus, dysmetria), bladder disturbances, and behavioral problems. SPG26 is caused by mutations in the B4GALNT1 gene (12q13.3), encoding Beta-1, 4 N-acetylgalactosaminyltransferase 1. SPG26 complex hereditary spastic paraplegia