Targeted proteomics performed on urine samples obtained from patients with MPS I, II, and VI showed increased expression of cartilage oligomeric matrix protein, insulin-like growth factor-binding protein 7, and beta-galactosidase in MPS II with neurological phenotype compared with MPS II with non-neurological phenotype [59]. The gene discussed is GLB1; the disease is mucopolysaccharidosis type 2.