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Genetics Home Reference: your guide to understanding genetic conditions
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MAT1A

Reviewed April 2007

What is the official name of the MAT1A gene?

The official name of this gene is “methionine adenosyltransferase I, alpha.”

MAT1A is the gene's official symbol. The MAT1A gene is also known by other names, listed below.

What is the normal function of the MAT1A gene?

The MAT1A gene provides instructions for producing the enzyme methionine adenosyltransferase. The enzyme is produced from the MAT1A gene in two forms, designated alpha and beta. The alpha form, called a homotetramer, is made up of four identical protein subunits. The beta form, called a homodimer, is made up of two of the same protein subunits. Both forms of the enzyme are found in the liver.

Both the alpha and beta forms of methionine adenosyltransferase help break down a protein building block (amino acid) called methionine. The enzyme starts the reaction that converts methionine to S-adenosylmethionine, also called AdoMet or SAMe. AdoMet is involved in transferring methyl groups, consisting of a carbon atom and three hydrogen atoms, to other compounds, a process called transmethylation. Transmethylation is important in many cellular processes. These include determining whether the instructions in a particular segment of DNA are carried out, regulating reactions involving proteins and lipids, and controlling the processing of chemicals that relay signals in the nervous system (neurotransmitters).

How are changes in the MAT1A gene related to health conditions?

hypermethioninemia - caused by mutations in the MAT1A gene

Approximately 15 mutations in the MAT1A gene have been found to reduce the activity of the methionine adenosyltransferase enzyme. Most of these mutations substitute one amino acid for another amino acid in the enzyme, causing it to process methionine less efficiently. Other mutations introduce a premature stop signal in the instructions for making the methionine adenosyltransferase enzyme. As a result, a shortened, nonfunctional enzyme is produced. A reduction in methionine adenosyltransferase function results in a buildup of methionine in the body and less efficient AdoMet production, and in severe cases can cause neurological problems.

Where is the MAT1A gene located?

Cytogenetic Location: 10q22

Molecular Location on chromosome 10: base pairs 80,271,819 to 80,289,956

The MAT1A gene is located on the long (q) arm of chromosome 10 at position 22.

The MAT1A gene is located on the long (q) arm of chromosome 10 at position 22.

More precisely, the MAT1A gene is located from base pair 80,271,819 to base pair 80,289,956 on chromosome 10.

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 MAT1A?

You and your healthcare professional may find the following resources about MAT1A helpful.

You may also be interested in these resources, which are designed for genetics professionals and researchers.

What other names do people use for the MAT1A gene or gene products?

  • MAT
  • MATA1
  • METK1_HUMAN
  • S-adenosylmethionine synthetase 1
  • SAMS
  • SAMS1
  • SAMS, liver-specific

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 MAT1A?

amino acid ; atom ; DNA ; enzyme ; gene ; methionine ; methyl ; nervous system ; neurological ; neurotransmitters ; protein

You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://www.ghr.nlm.nih.gov/glossary).

References

  • Biochemistry (fifth edition, 2002): Methionine Metabolism (http://www.ncbi.nlm.nih.gov/books/NBK22453/?rendertype=figure&id=A3252)
  • Chamberlin ME, Ubagai T, Mudd SH, Thomas J, Pao VY, Nguyen TK, Levy HL, Greene C, Freehauf C, Chou JY. Methionine adenosyltransferase I/III deficiency: novel mutations and clinical variations. Am J Hum Genet. 2000 Feb;66(2):347-55. (http://www.ncbi.nlm.nih.gov/pubmed/10677294?dopt=Abstract)
  • Chien YH, Chiang SC, Huang A, Hwu WL. Spectrum of hypermethioninemia in neonatal screening. Early Hum Dev. 2005 Jun;81(6):529-33. Epub 2004 Dec 19. (http://www.ncbi.nlm.nih.gov/pubmed/15935930?dopt=Abstract)
  • Chou JY. Molecular genetics of hepatic methionine adenosyltransferase deficiency. Pharmacol Ther. 2000 Jan;85(1):1-9. Review. (http://www.ncbi.nlm.nih.gov/pubmed/10674710?dopt=Abstract)
  • NCBI Gene (http://www.ncbi.nlm.nih.gov/gene/4143)
  • OMIM: METHIONINE ADENOSYLTRANSFERASE I, ALPHA (http://omim.org/entry/610550)
  • Smythies JR, Gottfries CG, Regland B. Disturbances of one-carbon metabolism in neuropsychiatric disorders: a review. Biol Psychiatry. 1997 Jan 15;41(2):230-3. Review. (http://www.ncbi.nlm.nih.gov/pubmed/9018395?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 healthcare professional. See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/handbook/consult/findingprofessional) in the Handbook.

 
Reviewed: April 2007
Published: July 21, 2014