Association of GSTT1 and GSTM1 gene polymorphisms with susceptibility to autoimmune diseases: A preliminary study

Abstract

Autoimmune diseases (ADs) are chronic conditions initiated by the loss of immunological tolerance to self-antigens. The aim of this study was to detrmine how polymorphisms of glutathione S-transferases T1 and M1 (GSTT1 and GSTM1) genes influences on the occurrence of two autoimmune diseases: multiple sclerosis (MS) and Hashimoto's thyroditis (HT). A multiplex polymerase chain reaction (PCR) was used to detect the deletions in GSTT1 and GSTM1 genes. Our results showed that patients with ADs had significantly higher (p < 0.05) frequency of GSTM1 null genotype compared to controls (44.4% vs. 0.0%, respectively). However, the homozygous deletion of both analyzed genes (GSTT1 null/GSTM1 null) showed no significant differences between these genotypes in the patients and controls (11.1% vs 0.0%, respectively). Our results showed that observed differences in the distribution of GSTT1 and GSTM1 null genotype in patients depending on the diagnosis (MS or HT) when compared to the same frequency of genotypes in control, were not statistically significant (p > 0.05). This study suggests the potential role of GSTM1 deletion on ADs susceptibility, but on the other hand this study should be repeated in other patients with the same or similar diagnosis of ADs.