Signal transducer and activator of transcription 4 (STAT4) G/T gene polymorphism in Egyptian systemic lupus erythematosus female patients

BackgroundSystemic lupus erythematosus (SLE) is a systemic autoimmune disease with complex genetic inheritance. Many reports have provided evidence that signal transducer and activator of transcription-4 (STAT4) may participate in the pathogenesis of SLE.Aim of the workThe aim was to investigate the clinical significance and possible association of STAT4 (G/T) genetic polymorphism and the susceptibility to SLE in a cohort of Egyptian female patients.Patients and methodsSixty-five Egyptian SLE female patients and 100 age and sex-matched unrelated female healthy blood donors who served as controls, were included in the study. STAT4 genotyping was performed by real time PCR-allelic discrimination technique.ResultsSTAT4 genotyping in patients revealed that 63.1% had GG, 32.3% GT and 6.15% wild (TT) genotype. There was a non-significant difference in the distribution of STAT4 genotypes between patients and controls. Vasculitis, photosensitivity and lupus nephritis were significantly increased in patients with the homomutant (GG and TT) compared to heteromutant (GT) genotype (p = 0.01, p = 0.04 and p < 0.01 respectively). Patients with a TT genotype had a significantly consumed C3 and C4 levels and higher anti-dsDNA positivity compared to those with GG and GT genotypes. Promoter polymorphism tended to be higher in juvenile-onset SLE cases.ConclusionsSTAT4 (G/T) polymorphism was not associated with an increased risk of SLE in Egyptian females. However, vasculitis, photosensitivity and renal involvement were significantly higher among patients harboring the homomutant genotypes. Genetic polymorphism may be an important determinant affecting disease progression and is associated with DNA positivity and younger age of onset.