MASCARO I.

The mucopolysaccharidoses (MPSs) are a group of rare lysosomal storage disorders caused by deficiency of enzymes catalyzing the stepwise degradation of glycosaminoglycans dermatan sulfate, heparan sulfate, keratan sulfate, chondroitin sulfate, and hyaluronic acid. There are seven groups of MPS, which are MPS-I (MPS-I-H or Hurler syndrome;...

Hyperphenylalaninemia (HPA) is a biochemical condition characterized by mildly or strongly elevated concentrations of the amino acid phenylalanine (Phe) in the blood. HPA is commonly diagnosed by newborn screening. The primary cause of HPA is phenylketonuria (PKU), an inborn error of metabolism characterized by persistently elevated plasma...

Tetrahydrobiopterin (BH4) is a natural and essential cofactor for the enzymatic hydroxylation of phenylalanine (Phe) and tyrosine (Tyr), and for two tryptophan hydroxylases, three nitric oxide synthases, and glyceryl-ethermonooxygenase. Five separate genetic conditions affecting BH4 synthesis or recycling have been identified so far, including...

Anderson-Fabry disease (AFD) is an X-linked lysosomal storage disorder caused by mutations in the a-galactosidase A gene on chromosome Xq22, resulting in a-galactosidase A enzyme deficiency. It is characterized by progressive accumulation of lipids (e.g., globotriaosylceramide) in the lysosomes of a variety of cell types, including neural...