Morquio B Disease. Disease Characteristics and Treatment Options of a Distinct GLB1-Related Dysostosis Multiplex

Int J Mol Sci. 2020 Nov 30;21(23):9121. doi: 10.3390/ijms21239121.


Morquio B disease (MBD) is an autosomal recessive GLB1-gene-related lysosomal storage disease, presenting with a peculiar type of dysostosis multiplex which is also observed in GALNS-related Morquio A disease. MBD may present as pure skeletal phenotype (pure MBD) or in combination with the neuronopathic manifestations seen in type 2 (juvenile) or type 3 (late onset) GM1 gangliosidosis (MBD plus). The main skeletal features are progressive growth impairment, kyphoscoliosis, coxa/genua valga, joint laxity, platyspondyly and odontoid hypoplasia. The main neuronopathic features are dystonia, ataxia, and intellectual/developmental/speech delay. Spinal cord compression occurs as a complication of spinal dysostosis. Chronic pain is reported, along with mobility issues and challenges with daily living and self-care activities, as the most common health concern. The most commonly reported orthopedic surgeries are hip and knee replacements. Keratan sulphate-derived oligosaccharides are characteristic biomarkers. Residual β-galactosidase activities measured against synthetic substrates do not correlate with the phenotype. W273 L and T500A are the most frequently observed GLB1 variants in MBD, W273L being invariably associated with pure MBD. Cytokines play a role in joint destruction and pain, providing a promising treatment target. In the future, patients may benefit from small molecule therapies, and gene and enzyme replacement therapies, which are currently being developed for GM1 gangliosidosis.

Keywords: GLB1; GM1 gangliosidosis; MPS4B; Mucopolysaccharidosis type 4; beta-galactosidase; developmental delay; dysostosis multiplex; dystonia; keratan sulfate; spondylo-epiphyseal dysplasia.

Publication types

  • Review

MeSH terms

  • Biomarkers
  • Cytokines / metabolism
  • Diagnosis, Differential
  • Disease Susceptibility
  • Gangliosidosis, GM1 / diagnosis
  • Gangliosidosis, GM1 / genetics
  • Gangliosidosis, GM1 / therapy
  • Humans
  • Mucopolysaccharidosis IV / diagnosis*
  • Mucopolysaccharidosis IV / etiology
  • Mucopolysaccharidosis IV / therapy*
  • Mutation
  • Phenotype
  • beta-Galactosidase / genetics


  • Biomarkers
  • Cytokines
  • beta-Galactosidase