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The information on this page was automatically extracted from online scientific databases.

What is the official name of the A2M gene?

The official name of this gene is “alpha-2-macroglobulin.”

A2M is the gene's official symbol. The A2M gene is also known by other names, listed below.

Read more about gene names and symbols on the About page.

What is the normal function of the A2M gene?

From NCBI GeneThis link leads to a site outside Genetics Home Reference.:

Alpha-2-macroglobulin is a protease inhibitor and cytokine transporter. It inhibits many proteases, including trypsin, thrombin and collagenase. A2M is implicated in Alzheimer disease (AD) due to its ability to mediate the clearance and degradation of A-beta, the major component of beta-amyloid deposits. [provided by RefSeq, Jul 2008]

From UniProt (A2MG_HUMAN)This link leads to a site outside Genetics Home Reference.:

Is able to inhibit all four classes of proteinases by a unique 'trapping' mechanism. This protein has a peptide stretch, called the 'bait region' which contains specific cleavage sites for different proteinases. When a proteinase cleaves the bait region, a conformational change is induced in the protein which traps the proteinase. The entrapped enzyme remains active against low molecular weight substrates (activity against high molecular weight substrates is greatly reduced). Following cleavage in the bait region a thioester bond is hydrolyzed and mediates the covalent binding of the protein to the proteinase.

How are changes in the A2M gene related to health conditions?

NCBI GeneThis link leads to a site outside Genetics Home Reference. lists the following diseases or traits (phenotypes) known or believed to be associated with changes in the A2M gene.
  • Alpha-2-macroglobulin deficiency
  • Alzheimer's disease
OMIM.orgThis link leads to a site outside Genetics Home Reference., a catalog designed for genetics professionals and researchers, provides the following information about the A2M gene and its association with health conditions.

Where is the A2M gene located?

Cytogenetic Location: 12p13.31

Molecular Location on chromosome 12: base pairs 9,067,708 to 9,115,962

(Homo sapiens Annotation Release 107, GRCh38.p2) (NCBIThis link leads to a site outside Genetics Home Reference.)

The A2M gene is located on the short (p) arm of chromosome 12 at position 13.31.

The A2M gene is located on the short (p) arm of chromosome 12 at position 13.31.

More precisely, the A2M gene is located from base pair 9,067,708 to base pair 9,115,962 on chromosome 12.

See How do geneticists indicate the location of a gene? in the Handbook.

Where can I find additional information about A2M?

You and your healthcare professional may find the following resources about A2M 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 A2M gene or gene products?

  • A2MD
  • CPAMD5
  • FWP007
  • S863-7

Where can I find general information about genes?

The Handbook provides basic information about genetics in clear language.

These links provide additional genetics resources that may be useful.

What glossary definitions help with understanding A2M?

amyloid ; beta-amyloid ; cytokine ; deficiency ; degradation ; enzyme ; mediate ; peptide ; protease ; protein ; proteinase ; thrombin ; trypsin

You may find definitions for these and many other terms in the Genetics Home Reference Glossary.

See also Understanding Medical Terminology.


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? in the Handbook.

Published: February 1, 2016