Methylmalonic Aciduria and Homocystinuria, cobalamin C (cblC) Type

Methylmalonic aciduria and homocystinuria, cblC type, is a defect in B12 metabolism. Patients may present with severe early-onset disease that includes megaloblastic and macrocytic anemia, failure to thrive, microcephaly, lethargy, and feeding difficulties. Neurologic symptoms may include seizures, hypotonia, intellectual disability, developmental delay, ataxia, optic atrophy, retinal degeneration, and pigmentary retinopathy. Late-onset cases may present with megaloblastic anemia and/or psychiatric disturbance, anorexia, irritability, fatigue, myelopathy, nephropathy, thromboembolic events, or dementia.

Tests Available

Forms and Documents

Test Details

MMACHC
  • Confirmation of a biochemical/clinical diagnosis
  • Carrier testing
  • Prenatal diagnosis in at risk pregnancies
  • Capillary Sequencing

Ordering

274
3-4 weeks
2-5 mL Blood - Lavender Top Tube
Oral Rinse (30-40 mL) | Buccal Swabs

Billing

81404x1
No
Yes
  • 270.4 Disturbances of sulphur-bearing amino-acid metabolism, Cystathioninemia, Cystathioninuria, Disturbances of metabolism of methionine, homocystine, and cystathionine Homocystinuria, Hypermethioninemia, Methioninemia
  • 270.9 Unspecified disorder of amino-acid metabolism
* For price inquiries please email zebras@genedx.com

References

  1. Rosenblatt, DS and Fenton, WA (2001) Inherited disorders of folate and cobalamin transport and metabolism . In: C.R. Scriver, A.L. Beaudet, W.S. Sly and D. Valle (Eds)The Metabolic and Molecular Basis of Inherited Diseases, McGraw-Hill, NY
  2. Lerner-Ellis et al. (2006) Nat. Genet. 38 (1):93-100 (PMID: 16311595)
  3. Wang et al. (2018) Metab Brain Dis : (PMID: 29374341)
  4. Lerner-Ellis et al. (2009) Hum. Mutat. 30 (7):1072-81 (PMID: 19370762)
  5. Stenson et al. (2014) Human Genetics 133 (1):1-9 (PMID: 24077912)
  6. Carrillo N, Adams D, Venditti CP. Disorders of Intracellular Cobalamin Metabolism. 2008 Feb 25 [Updated 2013 Nov 21]. In: Adam MP, Ardinger HH, Pagon RA, et al., editors. GeneReviews [Internet]. Seattle (WA): University of Washington, Seattle; 1993-2018.
  7. Stucki et al. (2012) Human Molecular Genetics 21 (6):1410-8 (PMID: 22156578)
  8. Rutsch et al. (2011) J. Inherit. Metab. Dis. 34 (1):121-6 (PMID: 20446115)
  9. Coelho et al. (2012) Nature Genetics 44 (10):1152-5 (PMID: 22922874)