KRAS and non-small cell lung carcinoma: The majority of KRAS mutations in NSCLC occur in codons 12 or 13, and the most frequent mutation is a transversion in which amino acid glycine is replaced by cysteine (G12C variants), accounting for 39–41% of KRAS mutations, followed by G12V (19–21%) and G12D (14–17%) [116, 117].