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GTR Home > Conditions/Phenotypes > Methylcobalamin deficiency type cblG

Methylcobalamin deficiency type cblG

Synonyms
Functional methionine synthase deficiency type cblG; HOMOCYSTINURIA-MEGALOBLASTIC ANEMIA DUE TO DEFECT IN COBALAMIN METABOLISM, cblG COMPLEMENTATION TYPE; HOMOCYSTINURIA-MEGALOBLASTIC ANEMIA, cblG COMPLEMENTATION TYPE; HOMOCYSTINURIA-MEGALOBLASTIC ANEMIA, cblG TYPE
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Disorders of intracellular cobalamin metabolism have a variable phenotype and age of onset that are influenced by the severity and location within the pathway of the defect. The prototype and best understood phenotype is cblC; it is also the most common of these disorders. The age of initial presentation of cblC spans a wide range: In utero with fetal presentation of nonimmune hydrops, cardiomyopathy, and intrauterine growth restriction. Newborns, who can have microcephaly, poor feeding, and encephalopathy. Infants, who can have poor feeding and slow growth, neurologic abnormality, and, rarely, hemolytic uremic syndrome (HUS). Toddlers, who can have poor growth, progressive microcephaly, cytopenias (including megaloblastic anemia), global developmental delay, encephalopathy, and neurologic signs such as hypotonia and seizures. Adolescents and adults, who can have neuropsychiatric symptoms, progressive cognitive decline, thromboembolic complications, and/or subacute combined degeneration of the spinal cord. [from GeneReviews]

Available tests

47 tests are in the database for this condition.

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Clinical tests (47 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: HMAG, MS, cblG, MTR
    Summary: 5-methyltetrahydrofolate-homocysteine methyltransferase

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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