Question

why is level of urine glycosaminoglycan secretion levels normal in I-cell disease but elevated in other lysosomal storage diseases

Answer 1

Lysosomal storage disorders are characterized by inherited deficiencies of lysosomal enzymes which is very essential for the degradation of mucopolysaccharides.

A failure of the metabolism induces selective accumulation of glycosaminoglycan in the blood, urine and body tissues.

A significant impairment of the responsible enzyme activity leads to the accumulation of the selective glycosaminoglycan.

I-Cell disease is an autosomal recessive disorder. The enzyme transfers phosphate to mannose residues on specific proteins. Without this marker, the proteins are instead excreted outside- the default pathway for proteins moving through the golgi apparatus. Lysosomes cannot function without these proteins.