As homozygous breeding of the conditional mouse model is not feasible due to embryonic lethality observed in biallelic KRaslsl–G12D/lsl–G12D embryos, CRISPR enables us to model and analyze the consequences of homozygous mutations in KRas, as NSCLC patients can present both genetic modifications (Chiosea et al., 2011; Ferrer et al., 2018). This evidence concerns the gene KRAS and non-small cell lung carcinoma.