A modified digestion-circularization PCR (DC-PCR) approach to detect hypermutation-associated DNA double-strand...

Hypermutation of immunoglobulin variable region genes occurs in B cells during an immune response, and is vital for the development of high-affinity antibodies. The molecular mechanism of the hypermutation reaction is unknown, but it seems to correlate with the generation of locus-specific, double-strand breaks. These DNA breaks have been measured by ligation-mediated polymerase chain reaction (LM-PCR), a technique that relies upon the ligation of a small linker to DNA breaks followed by the specific amplification of such breaks using combinations of locus- and linker-specific primers. Here, we describe a modified version of the digestion-circularization PCR (DC-PCR) technique, which can be used to amplify and measure DNA breaks directly.