CTCF	CCCTC-binding factor
DSBs	double-strand breaks
NHEJ	non-homologous end joining
HR	homologous recombination
IR	ionizing radiation
UV	ultraviolet
DDR	DNA damage response
MRN	MRE11-RAD50-NBS1
ssDNA	single-stranded DNA
D-loop	displacement loop
ChIP	chromatin immunoprecipitation
ICR	imprinting control region
TCR	T cell receptor
CBE	CTCF-binding element
TAD	topologically associated domain
PAR	poly(ADP-ribose)