Table 7.

MMACHC Pathogenic Variants Discussed in This GeneReview

DNA Nucleotide Change 1Predicted Protein ChangeReference Sequences
c.271dupA 2p.Arg91LysfsTer140 NM_015506​.2
NP_056321​.2
c.331C>T 3p.Arg111Ter
c.347T>Cp.Leu116Pro
c.394C>T 4p.Arg132Ter
c.440G>Cp.Gly147Ala
c.482G>A 5p.Arg161Gln
c.609G>A 6p.Trp203Ter

Variants listed in the table have been provided by the authors. GeneReviews staff have not independently verified the classification of variants.

GeneReviews follows the standard naming conventions of the Human Genome Variation Society (varnomen​.hgvs.org). See Quick Reference for an explanation of nomenclature.

1.
2.

Accounts for approximately 30%-50% of disease alleles in individuals of European ancestry [Lerner-Ellis et al 2006, Lerner-Ellis et al 2009, Fischer et al 2014]

3.

Common in people of Cajun and French Canadian ancestry [Lerner-Ellis et al 2009]

4.

Common in people of Indian and Middle Eastern ancestry [Lerner-Ellis et al 2009]; associated with a late-onset phenotype

5.

Associated with milder disease, and may be more common in individuals of Hispanic descent [Almannai et al 2017]

6.

Common in people of Chinese ancestry [Liu et al 2010]

From: Disorders of Intracellular Cobalamin Metabolism

Cover of GeneReviews®
GeneReviews® [Internet].
Adam MP, Feldman J, Mirzaa GM, et al., editors.
Seattle (WA): University of Washington, Seattle; 1993-2024.
Copyright © 1993-2024, University of Washington, Seattle. GeneReviews is a registered trademark of the University of Washington, Seattle. All rights reserved.

GeneReviews® chapters are owned by the University of Washington. Permission is hereby granted to reproduce, distribute, and translate copies of content materials for noncommercial research purposes only, provided that (i) credit for source (http://www.genereviews.org/) and copyright (© 1993-2024 University of Washington) are included with each copy; (ii) a link to the original material is provided whenever the material is published elsewhere on the Web; and (iii) reproducers, distributors, and/or translators comply with the GeneReviews® Copyright Notice and Usage Disclaimer. No further modifications are allowed. For clarity, excerpts of GeneReviews chapters for use in lab reports and clinic notes are a permitted use.

For more information, see the GeneReviews® Copyright Notice and Usage Disclaimer.

For questions regarding permissions or whether a specified use is allowed, contact: ude.wu@tssamda.

NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.