Congenital disorder of glycosylation

Doichol

Dolichol monophosphate

Mannose-6-phosphate.svg

Mannose-1-phosphate

DolicholMPM

Congenital disorder of glycosylation (CDG) is a group of rare genetic disorders that affect the process of glycosylation, which is the attachment of sugar molecules to proteins and lipids. This process is crucial for the proper functioning of many proteins and lipids in the body. CDGs can lead to a wide range of health problems, including developmental delays, neurological disorders, and organ dysfunction.

Classification

CDGs are classified based on the specific step in the glycosylation pathway that is affected. The two main types are:

• CDG-I: Disorders that affect the initial steps of glycosylation in the endoplasmic reticulum.
• CDG-II: Disorders that affect the processing of glycoproteins in the Golgi apparatus.

Symptoms

The symptoms of CDGs can vary widely depending on the specific type and severity of the disorder. Common symptoms include:

• Developmental delay
• Intellectual disability
• Seizures
• Hypotonia
• Liver disease
• Coagulopathy
• Failure to thrive

Diagnosis

Diagnosis of CDGs typically involves a combination of clinical evaluation, biochemical testing, and genetic testing. Biochemical tests may include analysis of serum transferrin isoforms, which can reveal abnormalities in glycosylation.

Treatment

There is currently no cure for CDGs, and treatment is primarily supportive and symptomatic. Management may include:

• Physical therapy
• Occupational therapy
• Speech therapy
• Nutritional support
• Management of specific symptoms such as seizures or liver disease

Prognosis

The prognosis for individuals with CDGs varies widely depending on the specific type and severity of the disorder. Some individuals may have mild symptoms and a normal lifespan, while others may have severe, life-threatening complications.

Research

Ongoing research is focused on better understanding the underlying mechanisms of CDGs, developing new diagnostic methods, and exploring potential treatments.

See also

• Genetic disorder
• Metabolic disorder
• Neurological disorder
• Endoplasmic reticulum
• Golgi apparatus