Summary
β-Mannosidase deficiency was demonstrated in fibroblasts of a girl who showed severe psychomotor retardation, bone deformities and gargoylism and recurrent skin and respiratory infections and who died at 20 years of age from bronchopneumonia. This first demonstration of a female patient confirms the autosomal recessive inheritance of β-mannosidosis. Further investigation of this gipsy family revealed β-mannosidosis in an older brother with a milder manifestation of gargoyl facial dysmorphology, mental retardation, hearing impairment and recurrent infections. β-Mannosidase activity was completely deficient in his cultured skin fibroblasts, leukocytes and plasma. In urine a characteristic disaccharide was present. Heterozygote levels of β-mannosidase were found in fibroblasts and/or plasma of the parents and one sister.

doi.org/10.1007/BF01800211, hdl.handle.net/1765/60345
Journal of Inherited Metabolic Disease
Department of Clinical Genetics

Kleijer, W., Hu, P., Thoomes, R., Boer, M., Huijmans, J., Blom, W., … Macek, M. M. (1990). β-Mannosidase deficiency: Heterogeneous manifestation in the first female patient and her brother. Journal of Inherited Metabolic Disease, 13(6), 867–872. doi:10.1007/BF01800211