Because the Kras codon 12 mutation is the most common mutation with 65% of total Kras mutations in cancer cells, while the codon 13 mutation is approximately 8% (Table 2), cancer cells with the Kras codon 12 mutation should be further considered as a screening target to confirm the relationship between the Kras genotype and the propofol effect on them. The gene discussed is KRAS; the disease is cancer.