ChIP using Mre11 (S. cerevisiae) antibody. Chromatin was immunoprecipitated with the antibody at the stated dilutions. Immunocomplexes were captured using polyacrylamide bead linked secondary antibodies. The resultant immunoprecipitate was probed by multiplex PCR, using primers 20 bp from the MAT locus double strand break (lower arrow) and 67 kb from the break (upper band, control locus).