Circular DNA is a product of the immunoglobulin class switch rearrangement

@article{Schwedler1990CircularDI,
  title={Circular DNA is a product of the immunoglobulin class switch rearrangement},
  author={Uta von Schwedler and Hans-Martin Jck and Matthias R. Wabl},
  journal={Nature},
  year={1990},
  volume={345},
  pages={452-456}
}
THE class of immunoglobulin is defined by the constant region of its heavy chain. When a B lymphocyte switches the class of heavy chain it produces, the constant region of µ-type heavy chain is replaced (reviewed in refs 1 and 2, and see ref. 3); this occurs through a DNA rearrangement that brings the gene segment encoding the new constant region close to the VDJ segment encoding the variable region. The pre-B-cell line 18-81, which switches from heavy chain µ to γ2b production in culture4,5… CONTINUE READING