Effect of Glutathione S-Transferase Gene Polymorphisms (Gstm1 and Gstt1) on Susceptibility to Uterine Myomas



Dehraisi SSM¹ ; Sadat SM² ; Tanha FD³ ; Aghasadegh MR² ; Bahramal G² ; Safarpour M⁴ ; Ebrahimi A⁴ Show Affiliations
Source: Tehran University Medical Journal Published:2015

Abstract

Background: Uterine myomas are benign tumors of the uterus and the most common solid pelvic tumors causing symptoms in approximately 25% of women in their reproductive years. However, its etiology and pathogenesis remain obscure; there is increasing evidence that this disease is inherited as a complex genetic trait. Recent studies indicated the involvement of glutathione S-transferase M1 (GSTM1) gene in the pathogenesis of this disease and current investigations are devoted to the other members of phase II detoxification system genes such as glutathione S-transferase T1 (GSTT1). Therefore, current study was carried out to investigate the distribution of GSTM1 and GSTT1polymorphisms in Iranian population in order to estimate possible impact of null-allele of each gene in development of this disease. Methods: 50 patients with uterine myomas diagnosed by ultrasonography and confirmed by histopathological examination after surgical intervention were recruited from subjects referred to the Pasteur Institute of Iran between November 2012 to September 2013. Accordingly, controls (n=50) were subjects without any of aforementioned gynecologic conditions. The genomic DNA was extracted from peripheral blood leukocytes using the salting out method. Subsequently, genotyping of GSTM1 and GSTT1 polymorphisms for gene deletions were carried out using Gap-polymerase chain reaction. Logistic regression analysis was applied to assess whether there was any risk increase among the cases compared to control group. The level of statistical significance was set at 0.05 and all analyses were conducted using the SPSS version 18.0 (SPSS Inc., Chicago, IL). Results: There was significant evidence that the distribution of the GSTM1 and GSTT1 genotypes differed between the patients and the controls with an allelic odds ratio (OR) of 3.56 (95%CI: 1.35-9.37, P=0.01) and 3.92 (95%CI: 1.4-10; P=0.009) respectively. Data analysis also revealed that individuals with both GSTM1 and GSTT1 null (-/-) genotypes had higher risk to develop the disease in comparison to the people with the both present (+/+) genotypes (OR:19.23, P=0.007). Conclusion: The findings suggest that the GSTM1 and GSTT1 genetic polymorphisms are associated with the development of uterine myomas in Iranian women which is in agreement with previous results obtained in other populations. However, the ethnic variations of polymorphisms shoulld be evaluated in detail and differences should be incorporated into investigations of susceptibility variants for this disease. © 2014, Tehran University of Medical Sciences (TUMS). All right reserved.