Synonyms: CDG syndrome type Ia | CDG-Ia | CDG1A | Carbohydrate deficient glycoprotein syndrome type Ia | Congenital disorder of glycosylation type 1a | Congenital disorder of glycosylation type Ia | Phosphomannomutase 2 deficiency
A rare congenital disorder of N-glycosylation and is characterized by cerebellar dysfunction abnormal fat distribution inverted nipples strabismus and hypotonia. 3 forms of PMM2-CDG can be distinguished: the infantile multisystem type late-infantile and childhood ataxia-intellectual disability type (3-10 yrs old) and the adult stable disability type. Infants usually develop ataxia psychomotor delay and extraneurological manifestations including failure to thrive enteropathy hepatic dysfunction coagulation abnormalities and cardiac and renal involvement. The phenotype is however highly variable and ranges from infants who die in the first year of life to mildly involved adults.
Data from Orphanet are used to provide information on a disease's name, synonym(s), and overview. Reference: Access aggregated data from Orphanet at Orphadata. Orphadata: Free access data from Orphanet. © INSERM 1999. Available on http://www.orphadata.org. Data version August 2026
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PMM2-CDG?
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Advocacy Organizations
Access to Life NGO
Access to Life is Ukraine’s first patient advocacy organization for rare genetic epilepsies, anchored in Dravet syndrome and SCN1A-related conditions. We support 600+ families nationwide, advocate for a national clinical protocol and drug access, and are building Ukraine’s National Patient Resource Centre and Patient Registry for genetic epilepsies.
Biliary Atresia and Liver Care Africa
To create awareness, provide support, and advocate for better healthcare services for individuals and families affected by biliary atresia and liver diseases.
CDG CARE
Our mission is to promote greater awareness and understanding of CDG, to provide information and support to families affected by CDG, and to advocate for and fund scientific research to advance the diagnosis and treatment of CDG.
CDG Canada
CDG Canada supports patients and families affected by Congenital Disorders of Glycosylation (CDG).
CDG UK
Supporting families in the UK affected by Congenital Disorders of Glycosylation.
Genetic Epilepsy Team Australia
Collaboration of research and care
Global Liver Institute
To improve the lives of individuals and families impacted by liver disease through promoting innovation, encouraging collaboration, and scaling optimal approaches to help eradicate liver diseases.
Legacy Bridges Foundation, Inc
The Legacy Bridges Foundation, Inc. is a 501(c)3 non-profit organization founded to bridge the gap to support, educate and advocate for individuals, families and caregivers of those living with epilepsy and other seizure related disorders. The Legacy Bridges Foundation, Inc. is dedicated to helping champions live a sustainable life through participation of essential supportive programs and service
Louisiana Metabolic Disorders Coalition
We support, educate, and advocate for patients & families affected by metabolic disorders.
Mississippi Metabolics Foundation
Our mission at Mississippi Metabolics Foundation (MMF) is to advocate, educate, and support families in MS affected by genetic metabolic disorders/inborn errors of metabolism (IEM's). MMF promotes initiatives and further advancements in legislation, education, research, clinical trials, studies, therapies, targeted treatments, and eventual cures for IEM’s and all rare diseases.
Portuguese Association for CDG
The APCDG aims to holistically support families affected by a CDG. Our mission based on the pillars of disease awareness, education, research and to subsequently, speed up the development of therapies that will significantly benefit patients and their family members. We believe that only by adopting a patient-centric approach we will find ways to improve their quality of life.
Rare Epilepsy Network (REN)
Improving outcomes of people with rare epilepsies through an innovative collaborative infrastructure that drives urgent, patient-centered research, educaiton and advocacy.
ReNU2 Foundation
ReNU2 Foundation supports families affected by RNU2-2-related neurodevelopmental disease. We foster collaboration, raise awareness, and advance research—pursuing a world where every family has testing, informed care, community, and treatment.
Uganda Alliance of Patients Organization
Supporting patients to access quality, safe and patient-centered healthcare services.
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Clinical Trials
For a list of clinical trials in this disease area, please click here.