DnA Melting Analysis (DMA) with a taqMan probe covering the mutation "hot spot" is a simple, sensitive, and "closed tube" method of mutation detection. However, DMA requires asymmetric pcR to produce single-stranded amplicons capable of interacting with taqMan probes. this makes quantitative analysis impossible owing to low amplification efficiency. Moreover, bi-strand mutation detection necessitates two independent pcRs. the SLAM-MS (Stem-Loop AMplicon Mutation Scanning) assay, in which symmetric PCR is performed using primers with 5'-universal primer sequence (UPS), has been developed to detect KRAS mutations. Some of the resulting amplicons, sense and antisense, adopt single-stranded stem-loop conformation and become unable to renature, but able to hybridize with taqMan probes. Hybrids of stem-loops and complementary taqMan probes are suitable for melting analysis and simultaneous bi-strand mutation scanning. in addition, the areas under the melting peaks are determined by the PeakFit software, a non-linear iterative curve fitting program, to evaluate the wild-type/mutant allele ratio. Thus, the SLAM-MS assay permits quantification of both the number of copies of the target sequence and the percentage of mutant alleles. for mutant enrichment, the SLAM-MS assay uses TaqMan probes as PCR blocking agents allowing an ~10 times higher mutation detection sensitivity than High Resolution Melting (HRM) assay. In basic cancer research, priority is given to large-scale (genome-and exome-wide) next generation sequencing (NGS) methods, which give a panoramic picture of defects in the cancer genome. However, for clinical diagnostics, a "targeted approach" is more often required, i.e. screening of previously known clinically important mutations, in particular in the KRAS, NRAS, BRAF, EGFR, and PIK3CA genes 1-7. In this case, the priorities are the feasibility of the method in a clinical laboratory, and its simplicity, performance, and sensitivity. These requirements are largely met by asymmetric PCR with a TaqMan probe covering the mutation "hot spot" and subsequent DMA (DNA Melting Analysis), which is one of the most simple, fast, and least costly methods to detect DNA mutations. Moreover, it is implemented in the "closed tube format" that avoids any additional manipulations and eliminates sample cross-contamination 8,9. The short length of the TaqMan probes (20-30 nucleotides) facilitates strong mismatch-induced changes in melting curves and clear discrimination of wild-type and mutant melt peaks. Computation of the areas under the peaks using specialized software permits quantification of the ratio of wild and mutant alleles 9. Furthermore, under special (suboptimal) PCR conditions, the TaqMan probes serve as blocking agents contributing to the enriched synthesis of mutant alleles 10. An inherent drawback of this method is the asymmetric mode of PCR necessary for accumulation of single-stranded amplicons ("targets" for TaqMan probes). This leads to a number of limitations: (i) a decrease in the amplification efficiency, ...