The K-ras gene is located on chromosome 12p12. Activating ras mutations can be found in human malignancies with an overall frequency of 15-20%. A high incidence of K-ras gene mutations has been reported in malignant tumors of the pancreas (80-90%), in colorectal carcinomas(30-60%), in hematopoietic neoplasia of myeloid origin (18-30%, K-and N-ras), and in seminoma(25-40%). In other tumors, a mutant ras gene is found at a lower frequency: for example, in breast carcinoma(0-12%, K-ras), glioblastoma and neuroblastoma.

Illustration of PyroMark KRAS assay results. The left pyrogram shows the wildtype sequence and the right pyrogram heterozygote G to A mutation in the second position of codon 12. Orange columns indicate the analyzed mutation.

In pancreatic carcinomas,the mutations areessentially seen only at the twelfth position, (codon or amino acid 12), with rare exceptions seen at codon 13. In non-small cell lung cancer (NSCLC), mutationally activated ras genes have been found most often in K-ras codon 12, less often in codons 13 and 61.

PyroMark KRAS can be used to genotype codons 12, 13 of the K-ras gene, and to perform allele quantification of individual positions in the same codons. In addition,rare mutations in codon 61 can be analyzed using the second primer set provided in the package.