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Methylcobalamin deficiency type cblE

Synonyms
HOMOCYSTINURIA-MEGALOBLASTIC ANEMIA, cblE COMPLEMENTATION TYPE; HOMOCYSTINURIA-MEGALOBLASTIC ANEMIA, cblE TYPE; Homocystinuria-Megaloblastic anemia due to defect in cobalamin metabolism, cblE complementation type; VITAMIN B12-RESPONSIVE HOMOCYSTINURIA, cblE TYPE
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Excerpted from the GeneReview: Disorders of Intracellular Cobalamin Metabolism
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.
Full text of GeneReview (by section):
Summary
GeneReview Scope
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Jennifer L Sloan
Nuria Carrillo
David Adams
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Available tests

48 tests are in the database for this condition.

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Clinical tests (48 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: MSR, cblE, MTRR
    Summary: 5-methyltetrahydrofolate-homocysteine methyltransferase reductase

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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