Figure 4.20. Isotype switching involves recombination between specific switch signals.

Figure 4.20Isotype switching involves recombination between specific switch signals

Repetitive DNA sequences that guide isotype switching are found upstream of each of the immunoglobulin C-region genes, with the exception of the δ gene. The figure illustrates switching in the mouse heavy-chain genes. Switching occurs by recombination between these repetitive sequences, or switch signals, with deletion of the intervening DNA. The initial switching event takes place from the μ switch region; switching to other isotypes can take place subsequently from the recombinant switch region formed after μ switching. S, switch region.

From: Structural variation in immunoglobulin constant regions

Cover of Immunobiology
Immunobiology: The Immune System in Health and Disease. 5th edition.
Janeway CA Jr, Travers P, Walport M, et al.
New York: Garland Science; 2001.
Copyright © 2001, Garland Science.

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