Interferon-gamma (IFN-γ) intronic variant (rs2430561) is a risk factor for systemic lupus erythematosus: Observation from a meta-analysis

Background:The role of interferon-gamma (IFN-gamma) in autoimmune disorders has been well documented. Elevated levels of IFN-gamma are observed in rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) and are linked with disease severity. Single nucleotide polymorphism in the intronic region of the IFN-gamma gene (+874 T > A rs2430561) has been associated with susceptibility to the development of RA and SLE; however, the reports remained contradictories. We conducted a meta-analysis using earlier published articles to reach a valid conclusion on the role of IFN-gamma polymorphism (+874 T > A) in autoimmune diseases. Materials and methods:Various online databases such as PubMed, Google Scholar, Science Direct, and Scopus were searched to find eligible reports for inclusion in the present analysis. Two independent authors extracted eligible studies and data. The meta-analysis was performed by comprehensive meta-analysis software (CMA) v.3.1. Trial sequential analysis was performed to test whether enough case-control studies have already been conducted worldwide to reach a valid observation. Results:Six published reports on the role of IFN-gamma +874 T > A in SLE and four in RA were found after searching various databases. However, out of those six studies in SLE, in one study, the distribution of genotypes was not following the hardy-Weinberg equilibrium. In RA, three studies were deviated out of four reports. Thus, a total of five studies comprising 1440 SLE patients and 1748 controls were considered for the present meta-analysis. Meta-analysis showed a significant association between IFN-gamma +874 T > A variants with susceptibility to SLE (homozygous comparison: p = 0.036, OR = 1.592, heterozygous model: p = 0.042, OR = 1.507, dominant model: p = 0.002, OR = 1.309). Conclusions:IFN-gamma +874 T > A variant is associated with predisposition to SLE development.

Automated summary

The role of interferon-gamma (IFN-gamma) in autoimmune disorders, such as rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), has been extensively studied. This meta-analysis aimed to determine the association between a specific polymorphism in the IFN-gamma gene and the susceptibility to RA and SLE. The results showed a significant association between the IFN-gamma polymorphism and the development of SLE.