highly significantp < 0.001
p < 0.05 was denoted as a significant difference (*), p < 0.01 was classified as a highly significant difference (**) and p < 0.001 was classified as an extremely difference (***). 3 Results 3.1 Generation of the LDLR-EGFP-Gluc knock-in HEK293 cell line We employed a dual detector cassette comprising open reading frames EGFP and Gluc, integrated directly upstream of the STOP codon located in exon 18 of the LDLR gene that would be transcribed in tandem with LDLR and subject to the same regulation ( Figure 1A ).