<prompt> In-situ DNA nick end labeling can quantitate:Fraction of cells in apoptotic pathwaysFraction of cells in S phasep53 gene productbcrabl gene  <response>: In situ DNA nick end - labeling In-situ method for detecting areas of DNA which are nicked during apoptosis. Terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labeling TUNEL is a method for detecting apoptotic cells that exhibit DNA fragmentation. 