Kisho

Kisho is an information platform, not a medical provider. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. All content is aggregated from publicly available sources (including ClinicalTrials.gov, PubMed, FDA.gov, and Orphanet) and is provided for informational purposes only. Clinical trial eligibility, treatment decisions, and any health-related actions should always be discussed with a qualified healthcare professional. Kisho does not endorse any specific therapy, organization, or clinical trial. Terms of use · Privacy policy

disorder of protein N-glycosylation - Clinical Profile, Genes & Research | Kisho | Kisho

Rare Disease

disorder of protein N-glycosylation

MONDO:0017740

Also known as:disorder of protein N-linked glycosylationprotein N-linked glycosylation disease

Overview

A disease that has its basis in the disruption of protein N-linked glycosylation.

OnsetCONGENITAL, ANTENATAL

Clinical Presentation

Built from Human Phenotype Ontology (HPO) phenotype annotations and GeneReviews clinical descriptions. Features represent findings documented across known cases — not an exhaustive list of possible symptoms.

No HPO annotations are available for this condition.

Age of onset: at birth, before birth.

GeneReviews

Clinical Guidance

Some features of PMM2-CDG are usually present in infancy, but may be too subtle to recognize and thus not come to medical attention. The clinical course varies by severity and includes the following typical presentations and stages: hydrops fetalis at the severe end, infantile multisystem presentation, late-infantile and childhood ataxia–intellectual disability stage, and an adult stable disability stage . Table 2. PMM2-CDG: Frequency of Select Features

Diagnosis

Drawn from GeneReviews diagnostic guidelines, newborn screening panel status (RUSP), and ClinGen gene-disease validity classifications. Reflects current clinical evidence and consensus where available.

GeneReviews

Diagnostic Criteria

PMM2-CDG is the most common of a group of disorders of abnormal glycosylation of N-linked oligosaccharides.

Suggestive Findings

PMM2-CDG should be suspected in a child, adolescent/adult, or fetus with the following findings. In a child. Developmental delay and hypotonia in combination with any of the following:

• Clinical findings

Source: GeneReviews — "PMM2-CDG"

Treatment

Compiled from FDA-approved drug records, orphan drug designations, and FDA Adverse Event Reporting System (FAERS) safety data. GeneReviews management guidance is included where available.

No approved treatments are currently available for disorder of protein N-glycosylation. The disease remains an area of unmet medical need.

GeneReviews

Management Guidelines

Evaluations Following Initial Diagnosis To establish the extent of disease and needs in an individual diagnosed with PMM2-CDG, the evaluations summarized (if not performed as part of the evaluation that led to the diagnosis) are recommended . Table 4. Recommended Evaluations Following Initial Diagnosis in Individuals with PMM2-CDG

Prognosis

Based on GeneReviews surveillance recommendations, HPO phenotype frequency and severity annotations, and published prevalence estimates from Orphanet and OMIM.

GeneReviews

Surveillance Guidelines

Table 6. Recommended Surveillance for Individuals with PMM2-CDG

System/Concern

Research Landscape

Sourced from ClinicalTrials.gov and PubMed. Publication types are classified using NLM-curated article metadata; research type breakdowns reflect the nature of published work for this disease.

No clinical trials have been registered for disorder of protein N-glycosylation.

215 publications have been identified in PubMed for disorder of protein N-glycosylation. Research spans Basic Science / Preclinical (63%), Review / Meta-Analysis (23%), and Diagnostic / Biomarker (6%).

Research Type	Count	% of Total
Laboratory research	135	63%

Data assembled from 4 of 12 sources · Last updated Oct 3, 2026, 10:51 AM UTC

MONDOHPOClinicalTrials.govFDAPubMedHGNCClinVarClinGenGeneReviewsOrphanetOMIMRUSP

Medical References

External Resources

Orphanet

European rare disease database

Orphanet:309347

GARD

Genetic and Rare Diseases Info Center

GARD:21335

Questions for Your Care Team

→Are there specialists or centers of excellence for this condition in my area?
→Is there a patient registry I should consider joining?

← Back to All Diseases

Feature	InfantileMultisystemPresentation	Late-Infantile ChildhoodAtaxia-ID Stage	Adult StableDisabilityStage	Comment
Hypotonia	Common	Common	Common	Both truncal axial
Faltering growth	Common	Common	NA	Often due to feeding issues /or vomiting
Developmental delay	Common	Common	NA	Adults have stable intellectual motor involvement.
Intellectual disability	NA	Common	Common	—
Ocular features	Common	Common	Common	Esotropia, strabismus in infants, retinitis pigmentosa, myopia. Cataracts may develop in adults.
Hyporeflexia	Common	Common	Common	—
Seizures	Reported	Reported	Reported	Typically responsive to medication
Ataxia	NA	Common	Common	—
Stroke-like episodes	Not reported	Reported	Not seen	Can present before age 2 yrs; not reported in adulthood
Peripheral neuropathy	Not reported	Common	Common	Observed at end of 1st decade
Abnormal subcutaneous fat distribution	Common	Common until early childhood, then disappears	Rare	Buttocks, suprapubic region, labia majora in females, inverted nipples; may disappear w/age
Characteristic facial features	Common	Common	Coarse facies reported	Changes w/age
Endocrine dysfunction	Reported	Reported	Reported	Hypoglycemia hypothyroidism reported in infants. Hypogonadotropic hypogonadism reported in adults
Osteopenia	Reported	Common	Common	—
Cardiac manifestations	Common	Rare	Rare	Pericardial effusions seen in infancy, cardiomyopathy structural heart defects reported but rare
Liver manifestations	Common	Common	Common	transaminases; may return to normal w/age
Renal manifestations	Reported	Reported	Reported	Multicystic kidneys w/normal function seen in children; proteinuria aminoaciduria w/nephropathy rarely reported
Immunologic	Rare	Rare	Rare	Recurrent infections consistent w/immunologic dysfunction minimal response to vaccines
Characteristic features on neuroimaging	Common	Common	Common	Cerebellar atrophy on MRI
Coagulopathy	Common	Common	Common	Both pro- anticoagulation factors are diminished; risk of bleeding life long, risk of DVT in adulthood ID = intellectual disability; NA = not applicable NIHF has been reported in 12 individuals along with antenatal complications of hydropic placenta and polyhydramnios.

Kisho

disorder of protein N-glycosylation

Overview

Clinical Presentation

Clinical Guidance

Diagnosis

Diagnostic Criteria

Suggestive Findings

Treatment

Management Guidelines

Prognosis

Surveillance Guidelines

Research Landscape

Medical References

External Resources

Orphanet

GARD

Questions for Your Care Team

Questions for Your Care Team

Differential Diagnosis

Clinical Guidance

Therapies Under Investigation

Clinical Trials

Recent Publications

disorder of protein N-glycosylation

Overview

Clinical Presentation

Clinical Guidance

Diagnosis

Diagnostic Criteria

Suggestive Findings

Treatment

Management Guidelines

Prognosis

Surveillance Guidelines

Research Landscape

Medical References

External Resources

Orphanet

GARD

Related Diseases

Questions for Your Care Team

Questions for Your Care Team

Differential Diagnosis

Clinical Guidance

Therapies Under Investigation

Clinical Trials

Recent Publications