The manifestations of beta-galactosidase deficiency range from Morquio syndrome type B (mucopolysacharidosis type IVB manifesting as spondyloepiphyso-metaphyseal osteodysplasia) to GM1 gangliosidosis (a more or less early neurodegenerative disease).
A Danish team describes for the first time the case of a young woman with limb-girdle myopathy without neurological damage or bone abnormalities, due to recessive mutations in the GLB1 gene.
- As a child, she ran more slowly than her peers, but this did not prevent her from riding a bicycle or roller skating.
- At the age of 19, she had difficulty climbing stairs.
- At the age of 30 she started to show signs of respiratory impairment and frequent falls, as well as the onset of cataracts and tinnitus.
- At 41 years of age, the amyotrophy is severe in the thighs and shoulders; she cannot get up from the floor without support and walks with a waddle in hyperlordosis.
- Her vital capacity is 52% of the theoretical vital capacity.
- The residual levels of β-galactosidase activity are 28% and 35%.
