Congenital Disorder of Glycosylation Type 1a (CDG-1a)
What is CDG-1a?
Congenital Disorder of Glycosylation Type 1a (CDG-1a), also known as pmm2-CDG, is a rare inherited genetic condition that causes a problem with the production of glycoproteins due to a lack of the specific enzyme known as phosphomannomutase (pmm2). This disorder affects multiple body systems, especially the nervous system.
It is estimated that 20% of babies born with CDG-1a with die within the first year of life. Over 800 individuals have been found to have CDG -1a worldwide. Approximately 50% of cases are from Scandinavian countries.
What are the symptoms of CDG-1a?
The symptoms of CDG-1a vary in severity in each individual. Symptoms experienced in infants include:
- Poor muscle tone
- Inverted nipples
- Developmental delays
- Difficulty feeding
- Failure to grow
- Enlarged liver and liver failure
- Fluid around the heart and heart failure
- It is estimated that 20% of infants born with CDG-1a will die within the first year of life
Individuals that survive infancy may also experience:
- Intellectual disabilities
- Inability to walk
- Stroke like episodes with temporary paralysis
- Reduced sensation in arms and legs
- Curvature of the spine
- Poor coordination
- Joint deformities
- Eye disorders with vision loss
- Blood clotting disorders
- Lack of or poor sexual development
What causes CDG-1a?
CDG-1a is an inherited genetic defect that must be passed by both the mother and father. Individuals that have the genetic defect but not the disorders are known as carriers. The inherited defect leads to a problem with the production of a specific enzyme known as phosphomannomutase (pmm2). This enzyme is necessary for many cellular and body system functions.
Are there treatment options for CDG-1a?
Treatment of CDG-1a is directed at symptom management and improvement of quality of life. There is no known cure for CDG-1a. Some treatment options include:
- Speech and physical therapy
- Nutritional support such as a feeding tube
- Surgery to assist with vision improvement
- Medications for seizures
- Wheelchairs and other mobility assist devices
- Close monitoring of liver, heart and nervous system function by doctors
Where can I find more information on CDG-1a?