Immunoglobulin gene diversification

Nancy Maizels1

  • 1Department of Immunology, University of Washington Medical School, Seattle, Washington 98195-7650, USA. maizels@u.washington.edu

Annual Review of Genetics
|November 16, 2005
PubMed

Three processes alter genomic sequence and structure at the immunoglobulin genes of B lymphocytes: gene conversion, somatic hypermutation, and class switch recombination. Though the molecular signatures of these processes differ, they occur by a shared pathway which is induced by targeted DNA deamination by a B cell-specific factor, activation induced cytidine deaminase (AID). Ubiquitous factors critical for DNA repair carry out all downstream steps, creating mutations and deletions in genomic DNA. This review focuses on the genetic and biochemical mechanisms of diversification of immunoglobulin genes.

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