Association of estrogen receptor alpha gene polymorphisms with cytokine genes expression in systemic lupus erythematosus.

Aim: To analyze the association of estrogen receptor alpha (OR alpha) gene polymorphisms with cytokine genes expression in patients with systemic lupus erythematosus (SLE) and controls.

Methods: Genomic DNA was extracted and polymorphisms of XbaI, Ukrainian (XX, Xx, or xx genotype) and PvuII (PP, Pp, or pp) in intron 1 of OR alpha gene were detected by polymerase chain reaction-restriction fragment length polymorphisms (PCR-RFLP) method. The messenger RNA (mRNA) levels of interleukin (IL)-10, IL-4, interferon (IFN)-gamma, and IL-2 were assessed by semiquantitative reverse transcription polymerase chain reaction (RT-PCR).

Results: In patients with SLE with PpXx genotype, IL-10 and IL-4 mRNA expression was higher (P < 0.001 and P = 0.013, respectively), while in patients with SLE with Ppxx genotype IFN-gamma and IL-2 mRNA expression was lower than in controls (P < 0.001). There was no significant difference in mRNA expression of 4 cytokines among controls with various genotypes.

Conclusion: OR alpha gene polymorphism may be associated with the expression of IL-10, IL-4, IL-2, and IFN-gamma in patients with SLE.