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Evolution of isotype switching
Women’s Health Research Faculty Publications
  • Janet Stavnezer, University of Massachusetts Medical School
  • Chris T. Amemiya
UMMS Affiliation
Department of Molecular Genetics and Microbiology
Publication Date
Document Type
Animals; Cytidine Deaminase; *Evolution, Molecular; *Gene Rearrangement; Humans; *Immunoglobulin Class Switching; Immunoglobulins; Mice; Variation (Genetics); Vertebrates

This review discusses evolution of the process of Ig heavy chain class switching, relating it to the first appearance of somatic hypermutation (SHM) of variable region genes. First, we discuss recent findings on the mechanism of class switch recombination (CSR) in mice and humans, and then review the mechanisms of expression of Ig heavy chain isotypes from fishes to mammals. Importantly, activation-induced cytidine deaminase (AID), which is essential for CSR and somatic hypermutation, is found in fishes. Although at least some fishes are likely to undergo SHM, CSR is highly unlikely to occur in this group. We discuss the first appearance of CSR in amphibians and how it differs in birds and mammals.

DOI of Published Version
Semin Immunol. 2004 Aug;16(4):257-75. Link to article on publisher's site
Related Resources
Link to article in PubMed
PubMed ID
Citation Information
Janet Stavnezer and Chris T. Amemiya. "Evolution of isotype switching" Vol. 16 Iss. 4 (2004) ISSN: 1044-5323 (Print)
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