Galactosamine-6 sulfatase

Galactosamine-6-sulfatase (GALNS) is an enzyme that plays a crucial role in the metabolism of certain complex carbohydrates in the body. It is involved in the breakdown of keratan sulfate, a type of glycosaminoglycan (GAG) that is found in various tissues, including the cornea, cartilage, and bone.

Function

GALNS is responsible for removing a specific sulfate group from the keratan sulfate molecule during its degradation process. This is a critical step in the metabolism of this GAG, as it allows for the subsequent breakdown of the molecule into simpler sugars that can be utilized by the body.

Genetics

The GALNS gene, located on chromosome 16, encodes the GALNS enzyme. Mutations in this gene can lead to a deficiency in GALNS activity, which in turn can result in the accumulation of keratan sulfate in various tissues. This can lead to a range of health problems, depending on the tissues affected.

Clinical significance

A deficiency in GALNS activity is the underlying cause of Mucopolysaccharidosis IV (MPS IV), also known as Morquio syndrome. This is a rare, inherited metabolic disorder characterized by skeletal abnormalities, vision problems, heart disease, and other symptoms. There are two types of MPS IV, known as MPS IVA and MPS IVB, which are distinguished by whether they are caused by mutations in the GALNS gene (MPS IVA) or another gene (MPS IVB).

See also

• Mucopolysaccharidosis
• Keratan sulfate
• Enzyme
• Metabolism