This suite of genetically defined FFPE cell line standards contains defined stoichiometric ratios of the seven variants of the K-Ras oncogene, for which testing is required to determine individual drug treatment regimens for colorectal cancer patients. The FFPE standards follow the launch of genetically defined genomic DNA (gDNA) standards. While the gDNA controls were primarily designed to support the validation of new diagnostic assays, the FFPE standards more closely recapitulate the way in which tumor biopsies are embedded for testing.