Tehran University of Medical Sciences International Journal of Hematology-Oncology and Stem Cell Research 2008-2207 19 4 2025 10 16 365 376 Mahdiyar Iravani Saadi Hematology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Nasrin Noshadi Hematology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Fakhroddin Hosseini Hematology, Oncology, and Bone Marrow Transplantation Department, Shiraz University of Medical Sciences, Shiraz, Iran Soodabeh Zare Hematology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Ramin Yaghoobi Shiraz Transplant Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Zahed Karimi 1) Department of Hematology,Oncology, and Bone Marrow Transplantation, Shiraz Unversity of Medical Sciences, Shiraz, Iran 2) Hormozgan University of Medical Sciences, Bandar Abbas, Hormozgan, Iran Zahra Ghahramani Hematology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran Mani Ramzi Shiraz University of Medical Sciences 2024 05 25 2025 08 09 Background: Beta-thalassemia is a hereditary blood disorder characterized by reduced synthesis of the beta-globin chain. MicroRNAs (miRs) are small RNA molecules that regulate gene expression and have been implicated in beta-thalassemia. To explore dysregulated miR-222 and miR-15a expression in transfusion-dependent beta-thalassemia and assess their potential associations with Torque Teno Virus and cytomegalovirus infections. Materials and Methods: This study included 57 TDT patients registered at the Thalassemia Clinic affiliated with the Hematology Research Center, Shiraz, Iran. The expression levels of miR-222 and miR-15a were analyzed using the real-time SYBR Green PCR method. TTV and CMV infections were detected by analyzing the presence of their genomic DNA using an in-house semi-nested PCR protocol. Results: The expression level of miR-222 was significantly up-regulated (47.5-fold, P≤0.001) in TDT patients compared to healthy controls. However, the expression of miR-15a in TDT patients was slightly decreased compared to healthy controls, but the difference was not statistically significant (P=0.193). TTV infection was observed in 21.1% of TDT patients, while CMV infection was detected in 5.2% of the patients. Although miR-222 and miR-15a gene expression levels were higher in TTV-positive patients compared to TTV-negative patients, the differences were not statistically significant (P=0.926 and P=0.243, respectively). Conclusion: MiR-222 was up-regulated in TDT patients, but miR-15a did not show a significant difference. TTV and CMV infections were detected, but their association with miR expression was not significant, possibly due to the small sample size. Larger studies are needed for a more comprehensive evaluation. https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/view/2249 https://ijhoscr.tums.ac.ir/index.php/ijhoscr/article/download/2249/1104