The lingering enigma of the allelic exclusion mechanism

Raul Mostoslavsky1, Frederick W Alt, Klaus Rajewsky

  • 1Howard Hughes Medical Institute, The Children's Hospital, Harvard Medical School, Boston, MA 02115, USA.

Cell
|September 2, 2004
PubMed

B lymphocytes produce diverse antibody specificities by "randomly" assembling antibody genes from germline segments. Yet, though each B lymphocyte has multiple allelic loci for the different antibody chains, each clonally derived mature B lymphocyte expresses a single species of antibody with a unique specificity via a process termed allelic exclusion. Despite some progress, the precise mechanism of allelic exclusion remains an enigma.

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