Reviewed October 2008
What is the official name of the MCCC2 gene?
The official name of this gene is “methylcrotonoyl-CoA carboxylase 2 (beta).”
MCCC2 is the gene's official symbol. The MCCC2 gene is also known by other names, listed below.
What is the normal function of the MCCC2 gene?
The MCCC2 gene provides instructions for making one part (the beta subunit) of an enzyme called 3-methylcrotonoyl-CoA carboxylase or 3-MCC. Beta subunits join with larger alpha subunits made from the MCCC1 gene; six of these pairings together form a functioning enzyme.
The 3-MCC enzyme is found in mitochondria, which are the energy-producing centers inside cells. This enzyme plays a critical role in breaking down proteins obtained from the diet. Specifically, it is responsible for the fourth step in the breakdown of leucine, an amino acid that is a building block of many proteins. This step converts a molecule called 3-methylcrotonyl-CoA to a molecule called 3-methylglutaconyl-CoA. Additional chemical reactions convert 3-methylglutaconyl-CoA into molecules that are later used for energy.
How are changes in the MCCC2 gene related to health conditions?
- 3-methylcrotonyl-CoA carboxylase deficiency - caused by mutations in the MCCC2 gene
More than 40 mutations in the MCCC2 gene have been identified in people with 3-methylcrotonyl-CoA carboxylase deficiency (also known as 3-MCC deficiency). Most of these mutations change single amino acids in 3-MCC, which severely reduces the activity of the enzyme. Other mutations prevent the production of any functional enzyme. As a result, leucine cannot be broken down properly, and byproducts of leucine processing build up to toxic levels in the body. These toxic substances can damage the brain, causing the characteristic signs and symptoms of 3-MCC deficiency.
Where is the MCCC2 gene located?
Cytogenetic Location: 5q12-q13
Molecular Location on chromosome 5: base pairs 70,883,114 to 70,954,532
The MCCC2 gene is located on the long (q) arm of chromosome 5 between positions 12 and 13.
More precisely, the MCCC2 gene is located from base pair 70,883,114 to base pair 70,954,532 on chromosome 5.
See How do geneticists indicate the location of a gene? (http://ghr.nlm.nih.gov/handbook/howgeneswork/genelocation) in the Handbook.
Where can I find additional information about MCCC2?
You and your healthcare professional may find the following resources about MCCC2 helpful.
You may also be interested in these resources, which are designed for genetics professionals and researchers.
- PubMed - Recent literature (http://www.ncbi.nlm.nih.gov/pubmed?term=(MCCC2%5BTIAB%5D)%20OR%20((MCCB%5BTIAB%5D)%20OR%20(3-methylcrotonyl-CoA%20carboxylase%5BTIAB%5D))%20AND%20((Genes%5BMH%5D)%20OR%20(Genetic%20Phenomena%5BMH%5D))%20AND%20english%5Bla%5D%20AND%20human%5Bmh%5D%20AND%20%22last%203600%20days%22%5Bdp%5D)
- OMIM - Genetic disorder catalog (http://omim.org/entry/609014)
Research Resources - Tools for researchers
- GeneCards (http://www.genecards.org/cgi-bin/carddisp.pl?id_type=entrezgene&id=64087)
- HUGO Gene Nomenclature Committee (http://www.genenames.org/data/hgnc_data.php?hgnc_id=6937)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/64087)
What other names do people use for the MCCC2 gene or gene products?
- MCCase subunit beta
- 3-methylcrotonyl-CoA carboxylase non-biotin-containing subunit
- non-biotin containing subunit of 3-methylcrotonyl-CoA carboxylase
See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/handbook/mutationsanddisorders/naming) in the Handbook.
What glossary definitions help with understanding MCCC2?
amino acid ;
You may find definitions for these and many other terms in the Genetics Home Reference
- Baumgartner MR, Almashanu S, Suormala T, Obie C, Cole RN, Packman S, Baumgartner ER, Valle D. The molecular basis of human 3-methylcrotonyl-CoA carboxylase deficiency. J Clin Invest. 2001 Feb;107(4):495-504. (http://www.ncbi.nlm.nih.gov/pubmed/11181649?dopt=Abstract)
- Dantas MF, Suormala T, Randolph A, Coelho D, Fowler B, Valle D, Baumgartner MR. 3-Methylcrotonyl-CoA carboxylase deficiency: mutation analysis in 28 probands, 9 symptomatic and 19 detected by newborn screening. Hum Mutat. 2005 Aug;26(2):164. (http://www.ncbi.nlm.nih.gov/pubmed/16010683?dopt=Abstract)
- Desviat LR, Pérez-Cerdá C, Pérez B, Esparza-Gordillo J, Rodríguez-Pombo P, Peñalva MA, Rodríguez De Córdoba S, Ugarte M. Functional analysis of MCCA and MCCB mutations causing methylcrotonylglycinuria. Mol Genet Metab. 2003 Nov;80(3):315-20. (http://www.ncbi.nlm.nih.gov/pubmed/14680978?dopt=Abstract)
- Gallardo ME, Desviat LR, Rodríguez JM, Esparza-Gordillo J, Pérez-Cerdá C, Pérez B, Rodríguez-Pombo P, Criado O, Sanz R, Morton DH, Gibson KM, Le TP, Ribes A, de Córdoba SR, Ugarte M, Peñalva MA. The molecular basis of 3-methylcrotonylglycinuria, a disorder of leucine catabolism. Am J Hum Genet. 2001 Feb;68(2):334-46. Epub 2001 Jan 17. (http://www.ncbi.nlm.nih.gov/pubmed/11170888?dopt=Abstract)
- Holzinger A, Röschinger W, Lagler F, Mayerhofer PU, Lichtner P, Kattenfeld T, Thuy LP, Nyhan WL, Koch HG, Muntau AC, Roscher AA. Cloning of the human MCCA and MCCB genes and mutations therein reveal the molecular cause of 3-methylcrotonyl-CoA: carboxylase deficiency. Hum Mol Genet. 2001 Jun 1;10(12):1299-306. (http://www.ncbi.nlm.nih.gov/pubmed/11406611?dopt=Abstract)
- NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/64087)
- Stadler SC, Polanetz R, Maier EM, Heidenreich SC, Niederer B, Mayerhofer PU, Lagler F, Koch HG, Santer R, Fletcher JM, Ranieri E, Das AM, Spiekerkötter U, Schwab KO, Pötzsch S, Marquardt I, Hennermann JB, Knerr I, Mercimek-Mahmutoglu S, Kohlschmidt N, Liebl B, Fingerhut R, Olgemöller B, Muntau AC, Roscher AA, Röschinger W. Newborn screening for 3-methylcrotonyl-CoA carboxylase deficiency: population heterogeneity of MCCA and MCCB mutations and impact on risk assessment. Hum Mutat. 2006 Aug;27(8):748-59. (http://www.ncbi.nlm.nih.gov/pubmed/16835865?dopt=Abstract)
The resources on this site should not be used as a substitute for
professional medical care or advice. Users seeking information about
a personal genetic disease, syndrome, or condition should consult with a qualified
See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.