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Updated: Jul 26, 2026
17:12
Profiling of Methyltransferases and Other S-adenosyl-L-homocysteine-binding Proteins by Capture Compound Mass Spectrometry (CCMS)
Published on: December 20, 2010
Transcobalamin II deficiency with methylmalonic aciduria in three sisters
H Bibi1, Z Gelman-Kohan, E R Baumgartner
1Pediatric Department, Clinical Genetic Institute Barzilai Medical Center, Ashkelon, Israel.
Journal of Inherited Metabolic Disease
|October 13, 1999
Summary
Transcobalamin II (TC II) deficiency causes megaloblastic anemia and potential neurological issues due to impaired vitamin B12 uptake. Early diagnosis and continuous vitamin B12 treatment are crucial for managing this rare genetic disorder.
Area of Science:
- Biochemistry
- Genetics
- Hematology
Background:
- Transcobalamin II (TC II) is essential for vitamin B12 (cobalamin, Cbl) transport and cellular uptake.
- Deficiency in TC II leads to intracellular Cbl deficiency, causing megaloblastic anemia and neurological complications.
Observation:
- A family of three sisters, of Moroccan origin, presented with symptoms suggestive of TC II deficiency.
- Diagnosis was suspected due to low unsaturated vitamin B12 binding capacity.
Findings:
- TC II deficiency was confirmed by the absence of detectable TC II via radioimmunoassay.
- Cultured fibroblasts from the patients were unable to synthesize TC II, confirming the genetic defect.
Implications:
- This case highlights the importance of continuous, long-term vitamin B12 treatment for managing TC II deficiency.
- Early diagnosis and intervention are critical to prevent irreversible neurological damage in patients with TC II deficiency.
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