Contributor: Gordon K. Klintworth
The mucopolysaccaridoses are an inherited disorders caused by defects in the degradation of  one or more glycosaminoglycan due to mutations in specific genes. Others probably recognized patients with these disorders before Hunter but his report in 1917 was the first definitive one. In 1919 Hurler documented two infants with a grotesque phenotype but with corneal clouding, a gibbus and mental retardation. Numerous distinct mucoploysaccharidoses are recognized. They include: mucopolysaccharidosis type I, mucopolysaccharidosis type II, mucopolysaccharidosis type III, mucopolysaccharidosis type IV, mucopolysaccharidosis type VI, and mucopolysaccharidosis type VII. The past designation of mucopolysaccharidosis type V no longer exists because the same  for that  entity, which is now called mucopolysaccharidosis type I-S, is involved in other phenotypes belonging to mucopolysaccharidosis type I. Likewise mucopolysaccharidosis type VIII has been discarded. The ocular tissues are affected in many of the mucopolysacharidoses.