Congenital disorders of glycosylation

What are congenital disorders of glycosylation (CDG)?

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.

Last updated on 05-01-20

Can individuals with a congenital disorder of glycosylation (CDG) have developmental delay?

Individuals with a CDG can have developmental delays. Depending on the individual, manifestations can range from normal development to severe developmental delay. Parents may begin to recognize a delay in development in their child around 4 months of age. Many children require early intervention therapy, including occupational, physical, and speech therapy.

Last updated on 05-01-20

Are there any advocacy organizations for individuals and families with a congenital disorder of glycosylation (CDG)?

Yes. You can view organizations providing information and supportive resources on our Web site by clicking on the Organizations tab on this page, or by clicking on the following link: glycosylation/resources/5

Last updated on 05-01-20

What is protein-losing enteropathy?

Protein-losing enteropathy is the abnormal loss of protein from the digestive tract, or the inability of the digestive tract to take in proteins.

Last updated on 05-01-20

What does it mean if a person has congenital disorder of glycosylation (CDG) type Ix?

If a person has CDG type Ix it means that the enzyme deficiency that causes the disorder is unknown. Some people are diagnosed with type Ix if they have not had genetic testing to determine a more specific subtype. Other individuals are diagnosed with type Ix because testing has not provided a specific diagnosis.

Last updated on 05-01-20

What are the symptoms and prognosis for individuals with congenital disorder of glycoslyation (CGD) type Ix?

Because CDG type Ix can be caused by different enzyme deficiencies (and the deficiency in this type is typically not known), the symptoms and prognosis cannot be predicted. The various types of CDG often have different symptoms and a different prognosis. Even individuals with the same type of CDG may not have the same symptoms and prognosis.

Last updated on 05-01-20

Name: CDG CARE PO Box 38832
Colorado Springs, CO, 80937,
Toll Free: (866) 295-7910 Email: Url:
Name: Portugese Association for CDG and other Rare Metabolic Diseases APCDG-DMR Url:
Diagnosis of CDG National Society of Genetic Counselors. Reference Link Sparks SE & Krasnewich DM. Congenital Disorders of N-linked Glycosylation Pathway GeneReviews. 01/30/2014; Reference Link

Connect with other users with Congenital disorders of glycosylation on the RareGuru app

Do you have information about a disease, disorder, or syndrome? Want to suggest a symptom?
Please send suggestions to RareGuru!

The RareGuru disease database is regularly updated using data generously provided by GARD, the United States Genetic and Rare Disease Information Center.

People Using the App

Join the RareGuru Community

To connect, share, empower and heal today.

People Using the App