en پزشکی مولکولی Molecular Medicine تحقيقي Original Paper <strong>Background and objectives: </strong>Coronary artery disease (CAD) refers to stenosis or obstruction of coronary artery due to atherosclerosis or clotting. The aim of this study was to evaluate possible association of serum miRNA-197 (miR-197) expression as a biomarker for CAD diagnosis.<br> <strong>Methods:</strong> In this study, 100 patients with CAD who had angiography and vascular transplantation were selected. Expression of miR-197 was evaluated using real-time RT-PCR technique and the SYBR Green method. The Pearson&#39;s correlation coefficient was used to determine relationship of miR-197 expression and severity of coronary artery disease. The t-test was used to determine significance of expression of miR-197 in the study groups. All statistical analyses were carried out in SPSS 16 and at significance of 0.05.<br> <strong>Results:</strong> The results showed a <strong>direct relationship </strong>between miR-197 expression and CAD severity. The relative expression of miR-197 in the CAD patients was significantly higher than that in control subjects (P<0.004).<br> <strong>Conclusion:</strong> It seems that miR-197 can be considered as an indicator of coronary endothelial cell function. This microRNA could be used as a biomarker for CAD prognosis and treatment progression.<span dir="RTL"></span> MIRN197 microRNA,human,Coronary Artery Disease,U6 small nuclear RNA, 27 31 http://mlj.goums.ac.ir/browse.php?a_code=A-10-941-1&slc_lang=en&sid=1 Shahram Zehtabian rosagol1343@gmail.com 100319475328460021041 100319475328460021041 No Department of Biology, Faculty of Biological Science, Islamic Azad University, North Tehran Branch, Tehran, Iran reza alibakhshi ralibakhshiy@gmail.com 100319475328460021042 100319475328460021042 Yes kermanshah university of medical sciences Seyed Yousef Seyedena y.seyedena@yahoo.com 100319475328460021043 100319475328460021043 No Department of biology, faculty of Biological science, Islamic Azad University, North Tehran Branch, Tehran, Iran Ali-Reza Rai alireza_rai@yahoo.com 100319475328460021044 100319475328460021044 No kermanshah university of medical sciences