By sequencing the regions of the 3′ UTR of KRAS in multiple non-small cell lung cancer (NSCLC) cases, rs61764370 (also known as the KRAS-variant) was identified as the first single nucleotide polymorphism (SNP) within a let-7 complementary site to be a biomarker for NSCLC risk [12]. Here, KRAS is linked to non-small cell lung carcinoma.