The human flap endonuclease FEN1 is a crucial enzyme involved in DNA replication, repair, and recombination. It recognizes and cleaves 5'-unannealed DNA flaps and is necessary for processing Okazaki fragments and repairing DNA damage. Its absence results in abnormal phenotypes, increased frequency of DNA repeats and recombination events, growth defects, and hypersensitivity to DNA-damaging agents. FEN1 deficiency increases apoptotic cell death after ionizing radiation treatment, suggesting its potential as a therapeutic target for cancer treatment. Is the molecule effective to this assay?