Congenital Disorders Of Glycosylation
Congenital disorders of glycosylation (CDG) are a group of inherited metabolic disorders that affect a process called glycosylation. Glycosylation is the complex process by which all human cells build long sugar chains that are attached to proteins, which are called glycoproteins. There are many steps involved in this process, and each step is triggered by a type of protein called an enzyme. Individuals with a CDG are missing one of the enzymes that is required for glycosylation. The type of CDG that a person has depends on which enzyme is missing. Currently, there are 19 identified types of CDG. CDG type IA is the most common form. The symptoms of CDG vary widely among affected individuals. Some people have severe developmental delay, failure to thrive, and multiple organ problems, while others have diarrhea, low blood sugar (hypoglycemia), liver problems, and normal developmental potential.