i-BLESS: ultra-sensitive method for detection of DNA double-strand breaks

Here, we present i-BLESS, a method for direct genome-wide DNA double-strand break labeling in cells immobilized in agarose beads. i-BLESS has three key advantages: (i) it is the only unbiased method applicable to yeast, (ii) it achieves sensitivity of detecting one break in 100,000 cells, (iii) it eliminates high background level while still allowing for fixation of samples. The method allows detection of ultra-rare breaks.