• Is there any association between SOD1 and TNF-α gene promoters methylation and type 2 diabetes?
  • Zahra Moradi Shahgharieh,1 Effat Farrokhi,2,* Mehrnaz sadat Ravari,3
    1. MSc student, Cellular and Molecular Research Center, Basic Health Sciences Institute, Shahrekord University of Medical Sciences, Shahrekord , Iran
    2. Asistant professor, Department of Molecular Medicine, School of Advanced Technologies, Shahrekord University of Medical Sciences, Shahrekord, Iran


  • Introduction: Type 2 diabetes is a multifactorial disease with the effects of both hereditary and environmental factors. Although hereditary factors play a significant role in the development of type 2 diabetes, heredity is not the only cause of the disease and a proportion of the disease is caused by environmental factors and lifestyle. The precise molecular mechanisms of type 2 diabetes have not been identified to date. Therefore, it is important to study the possible genes involved in the pathogenesis of the disease. Epigenetic mechanisms appear to play important roles in the possible pathways of the disease. The purpose of this study was to identify the role of methylation, as a epigenetic mechanism, in the pathogenesis of type 2 diabetes, which could actually be a basis for more extensive studies.
  • Methods: In this study DNA was isolated from the peripheral blood mononuclear cells (PBMC) of 31 type 2 diabetic patients with a history of more than 5 years, 30 patients with a history of less than 5 years and 30 control subjects. Bisulfite treatment and nested PCR was carried out and finally sequencing was performed in order to investigation the methylation status of TNF-α and SOD1 gene promoters.
  • Results: There was no association between SOD1 and TNF-α gene promoters methylation and type 2 diabetes in the studied groups. Our results revealed that CpG sites of SOD1 gene promoter were methylated in females in compared with males in the patients. Also data have shown that CpG22 of SOD1 gene promoter in the patients with a history of less than 5 years was higher methylation.
  • Conclusion: According to the studies, whereas SOD1 and TNF-ɑ play a crucial role in the pathology of the disease, the DNA methylation levels of the SOD1 and TNF-ɑ promoters in blood are not related to the occurrence of type 2 diabetes. The difference in the methylation status of the promoter of SOD1 in female and male patients showed the role of gender in the pathology of type 2 diabetes.
  • Keywords: type 2 diabetes, epigenetic, methylation, SOD1, TNF-ɑ