XRCC5 and plasma cell myeloma: Many efforts have been made to develop the evaluation of the therapeutic effect of myeloma patients based on NHEJ (WHSC1, XRCC5 (KU80), PNKP, POLL), HR (EXO1, BLM, RPA3, RAD51, MRE11A and ATM) genes in MM patients 8-12.