part_of part of part of DNA catabolic process apoptotic DNA fragmentation biological_process DNA fragmentation in response to apoptotic signals is achieved through the activity of apoptotic nucleases. In human, these include DNA fragmentation factor (DFF) or caspase-activated DNase (CAD) and endonuclease G (Endo G) (reviewed in PMID:15723341). Caution is needed when apoptotic DNA laddering assays show presence of fragmented DNA. A positive assay may simply reflect the end point of a whole apoptotic process. Unless clear experimental evidence is available to show that a gene product is directly involved in fragmenting DNA, please do not annotate to GO:0006309 'apoptotic DNA fragmentation' and consider annotating instead to a more upstream process such as, e.g., GO:0042981 'regulation of apoptotic process', GO:0006915 'apoptotic process', GO:0097190 'apoptotic signaling pathway'. Also, note that gene products involved in compartmentalization of apoptotic nucleases and in activation or repression of their enzymatic activity should be annotated to the regulation term GO:1902510 'regulation of apoptotic DNA fragmentation' or to one of its children (see PMID:15723341). DNA catabolism during apoptosis DNA fragmentation involved in apoptotic nuclear change DNA catabolic process during apoptosis endonucleolytic DNA catabolic process involved in apoptosis chromatinolysis DNA fragmentation GO:0006309 Reactome:R-HSA-140342 The cleavage of DNA during apoptosis, which usually occurs in two stages: cleavage into fragments of about 50 kbp followed by cleavage between nucleosomes to yield 200 bp fragments. apoptotic nuclear changes