en Molecular Genetics & Genomics Molecular Genetics & Genomics مقاله کامل Full Length/Original Article <strong>Background: </strong>Colorectal cancer (CRC) is the third most common&nbsp;cancer&nbsp;worldwide. microsatellite instability (MSI) is a molecular marker of a deficient mismatch repair system and happens in almost 15% of&nbsp;CRCs. Because of a wide frequency of MSI⁺ CRC in Iran compared to other parts of the world, the importance of screening for this type of cancer is highlighted.<strong> Methods: </strong>The most common MSI detection technique is a fluorescent PCR-based method in which fragments are analyzed by capillary electrophoresis (CE). This technique is very time-consuming, difficult, and expensive. We sought to develop and evaluate a proper method with high accuracy, specificity, and sensitivity to screen the MSI⁺CRC. A high-resolution melting (HRM) analysis procedure is relying on the analysis of the melting curve attributes. Low cost, feasibility, high specificity, and sensitivity are outstanding attributes of HRM analysis. <strong>Results: </strong>Five mononucleotide microsatellite markers, including BAT-25, BAT-26, NR-21, NR-24, and NR-27, in 25 archival CRC tumor tissue samples were compared with normal tissue adjacent using HRM method. The specificity and sensitivity of BAT-25 with HRM method were 100% compared to CE, while other markers had lower sensitivity. However, when all the markers were considered together, the sensitivity and specificity became 100%. The number of MSI⁺ samples was 56%, which shows a higher ratio than previous Iranian studies. The highest MSI was related to BAT-26 (52%). <strong>Conclusion: </strong>The HRM method is much simpler and more cost-effective than current MSI techniques, and its sensitivity and accuracy are comparable. Therefore, it can serve as an alternative method in cases where CE is unavailable. Biomarkers, Microsatellite instability, Colorectal cancer 70 76 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-3852-1&slc_lang=en&sid=1 Nafiseh Raji nafisehraji@gmail.com 0000-0002-4130-9659 No National Institute of Genetic Engineering and Biotechnology Tayebeh Majidi Zadeh majidi@nigeb.ac.ir 0000-0002-2198-223X No National Institute of Genetic Engineering and Biotechnology Pegah Babaheidarian babaheidarian.p@iums.ac.ir 0000-0001-9488-7228 No Iran University of Medical Sciences Massoud Houshmand nafisehraji@gmail.com 0000-0002-2198-223X Yes National Institute of Genetic Engineering and Biotechnology