LoxP sites were inserted into introns 2 and 3 using long-chain single-stranded oligodeoxynucleotides (lsODNs) and sgRNAs with CRISPR/Cas9 technology. LxoP sites were inserted at chr8:88125028-88125029 and chr8:88125950-88125951 (build GRCm38). (J:282373)