Using an sgRNA (targeting AGGCAGCTGATTCTACCAGA) and an ssODN template (AATGGGTGTGTGTTTTTGGGCAAGTATGCTGCATATACAGTTTCAATGGCTTTTCTCAAGGCAGCTGATCCTACGAGTCGGTCTGAAATCTGAAAAATCAAAAGGAGAGTTAACCAGATCACACTTG) with CRISPR/Cas9 technology, glutamic acid codon 268 (GAA) was changed to glycine (GGA) (c.803A>G, p.E268G). (J:324056)