FCDGC’s vision is to provide the best integrated clinical care for congenital disorders of glycosylation (CDG) in the nation so that, from the patient’s perspective, the services delivered are consistent and coordinated.

A strong patient association, committed clinicians and a devoted group of scientists has formed a virtual consortium over the last decade and have closely collaborated to improve patient outcomes. Partners in our consortium have collaborated for many years—sharing knowledge, individualizing therapy, organizing patient conferences, and supporting physicians caring for individuals with CDG patients. We have improved patient care in this rare disease. On this foundation we have set out to establish a nationwide network of regional centers to relieve decades of unresolved questions, address knowledge gaps, develop treatment and meet currently unmet patient needs.

About Congenital Disorders of Glycosylation

Congenital disorders of glycosylation (CDG) is a large group of rare, inherited disorders that affect a complex process in the body call glycosylation. Most children who have CDG have neurological issues and symptoms, developmental problems, growth delays, and problems with organs not working like they should.

Congenital means that CDG is a condition that happens at or before birth. Notice that “disorders” is plural. This is because CDG is not just one disorder, but rather, a group of disorders. There are many types. Which type your child has depends on which body system is affected.

Glycans are sometimes called “sugar trees,” “antennas,” or “sugar chains” by health care providers. They are built from sugar “building blocks.” When some people hear sugar, they think of blood sugar, blood glucose, or diabetes. This is not the case with glycans, which are not used for burning calories. Glycosylation is the process of creating, changing, and attaching these sugar building blocks to proteins and lipids. When the sugar building blocks attach to proteins, they are called “glycoproteins.” When the sugar building blocks attach to lipids, they are called “glycolipids.”

When someone has CDG, his or her body cannot properly add or attach the sugar building blocks to proteins or lipids. Every single system in the body needs the process of glycosylation so the body can function normally. This is why people with CDG have many health problems—because many body systems are affected by glycosylation not working correctly.

CDG Overview and Introduction to the FCDGC


FCDGC’s mission is to improve clinical symptoms as well as improve quality of life and life expectancy of individuals with congenital disorders of glycosylation through advancing and sharing knowledge, developing and validating new diagnostic tools, and exploring therapeutic options to restore appropriate glycosylation.


Define natural history, validate patient reported outcome and share knowledge on Congenital Disorders of Glycosylation; Develop and validate new biochemical diagnostic techniques and therapeutic biomarkers for clinical trials; Restore appropriate glycosylation in Congenital Disorders of Glycosylation to improve clinical symptoms and quality of life of patients and their families.

Diseases Studied

All types of congenital disorders of glycosylation (CDG) are of interest to the consortium. These may include, but are not limited to, the following types:

  • PMM2-congenital disorder of glycosylation (PMM2-CDG, also known as congenital disorder of glycosylation type Ia)
  • PGM1-congenital disorder of glycosylation (PGM1-CDG, also known as congenital disorder of glycosylation type It)
  • SLC35A2-congenital disorder of glycosylation (SLC35A2-CDG, also known as congenital disorder of glycosylation type IIm)
  • NGLY1 Deficiency [NGLY1-CDDG (congenital disorder of deglycosylation)]
  • ALG13-congenital disorder of glycosylation (ALG13-CDG, also known as congenital disorder of glycosylation type Is)

Current Studies

  • Clinical and Basic Investigations into Congenital Disorders of Glycosylation (NCT#04199000) · currently enrolling patients
  • Large-Scale Metabolomic Profiling for the Diagnosis of Inborn Errors of Metabolism (NCT#04201067) · not recruiting

CDG Leadership

  • Dr. Eva Morava-Kozicz · Admin core leader/Clinical trials
  • Dr. Gerard Berry · Admin core leader
  • Dr. Christina Lam · Natural History Studies
  • Dr. Hudson Freeze · Biomarker and Diagnostics
  • Dr. Surendra Dasari · Pilot and feasibility projects
  • Dr. Tamas Kozicz · Career enhancement
  • Dr. Eric Polley · Data management and primary DMCC contact

Our History

Congenital disorders of glycosylation (CDG) consist of more than 130 different inborn errors of metabolism at an estimated overall incidence of greater than 1 in 100,000. While these disorders were first genetically defined in the 1990s, there is no data available on their natural history, no comprehensive patient registry, no reliable screening tests for many types, and large gaps in clinical trial readiness. In response, a nationwide network of 13 sites total (including 9 clinical sites) was established to: define the natural history; validate patient-reported outcomes and share CDG knowledge; develop and validate new biochemical diagnostic techniques and therapeutic biomarkers to increase clinical trial readiness; and evaluate whether dietary treatments restore appropriate glycosylation to improve clinical symptoms and quality of life.

As with all RDCRN consortia, patients are key partners in research.

The consortium leverages cross-disciplinary, team-based clinical science to address decades of unresolved questions; increase clinical trial readiness; advance and share knowledge, awareness and education on CDG; and, most importantly, develop treatments and meet unmet patient needs.