Association of the Genetic Variants in the Endoplasmic Reticulum Aminopeptidase 2 Gene With Ankylosing Spondylitis Susceptibility Publisher Pubmed



Ebrazeh M¹ ; Ezzatifar F^{2, 3} ; Torkamandi S⁴ ; Mohammadi FS⁵ ; Salimifard S⁶ ; Gowhari Shabgah A⁷ ; Hemmatzadeh M⁸ ; Aslani S⁹ ; Babaie F¹⁰ ; Jadidiniaragh F^{11, 12} ; Gholizadeh Navashenaq J¹³ ; Mohammadi H^{14, 15}
Source: International Journal of Rheumatic Diseases Published:2021

Abstract

Background: Genetic polymorphisms in the endoplasmic reticulum aminopeptidase gene ERAP2 has been attributed with the etiopathogenesis of ankylosing spondylitis (AS). Here we assessed the association of ERAP2 gene single nucleotide polymorphisms (SNPs) with AS predisposition in Iranian patients and determined their effect on the inflammatory state of the patients. Methods: For genotyping of rs2548538, rs2287988, and rs17408150 SNPs using a real-time allelic discrimination approach, DNA was extracted from the whole blood of 250 AS patients and 250 healthy individuals. RNA of the peripheral blood mononuclear cells was separated, cDNA was synthesized, and transcriptional levels of cytokines, including interleukin (IL)-17A, IL-23, IL-10, and transforming growth factor-β, were measured. Enzyme-linked immunosorbent assay was used to measure the serum concentration on the cytokines. Results: Three ERAP2 gene SNPs were not associated significantly with AS risk. Nonetheless, rs2287988 and rs17408150 SNPs showed statistically significant association with susceptibility to the disease in those AS patients who were positive for human leukocyte antigen (HLA)-B27. Transcriptional level and serum concentration of IL-17A and IL-23 were higher, but those of IL-10 were lower in both AS patients and the HLA-B27-positive patient group relative to the control group. Nevertheless, ERAP2 gene SNPs in the HLA-B27-positive AS patients did not affect the transcription level and serum concentration of cytokines. Conclusions: ERAP2 gene rs2287988 and rs17408150 SNPs are associated with susceptibility to AS, but they are probably not determining the levels of IL-17A, IL-23, and IL-10 in this disease. © 2021 Asia Pacific League of Associations for Rheumatology and John Wiley & Sons Australia, Ltd