GLB1 and mucopolysaccharidosis type 4B: The MPS IVB subtype is described as a non-neurological disease, however, it is worth noting that dysfunction in the same enzyme, β-galactosidase, is responsible for both MPS IVB and GM1 gangliosidosis, a severe neurodegenerative disease, while positions of mutations in the GLB1 gene determine the disease symptoms [17].