Autoimmune Regulator Gene Polymorphisms in Egyptian Systemic Lupus Erythematosus Patients: Preliminary Results

Abstract

Background. Systemic lupus erythematosus (SLE) is a systemic autoimmune disease. The autoimmune regulator (AIRE) is a master regulator of self-tolerance development. AIRE mutations lead to the development of autoimmune polyglandular syndrome type 1 while AIRE polymorphisms have been linked to organ-specific autoimmunity. The study is aimed at addressing the association between AIRE polymorphisms, rs2075876 (G > A) and rs760426 (A > G), and SLE susceptibility and expression in Egyptian patients. Methods. Ninety-nine patients were included. One hundred and ten, and 123 control subjects were genotyped for rs2075876 and rs760426, respectively. Lupus severity was assessed using the Lupus Severity of Disease Index and Lupus Severity Index (LSI). Systemic Lupus International Collaborating Clinics (SLICC)/American College of Rheumatology (ACR) damage index was considered. Genotyping was done using StepOne Real-Time PCR. Results. AIRE rs760426 GG was more frequent in the patients under the genotype level (14.1% vs. 4.9%, $p=0.032$ ) and recessive model (14.1% vs. 4.9%, $p=0.017$ , $\text{OR}=3.2$ (1.2-8.7)). Musculoskeletal involvement and nephritis were associated with AIRE rs2075876 under the dominant (97.9% vs. 80.8%, $p=0.009$ , $\text{OR}=11$ (1.3-89.2)) and recessive models (100% vs. 69.3%, $p=0.032$ ), respectively; and both were linked to AIRE rs2075876 at the allelic level: 98.3% vs. 85%, $p=0.005$ , $\text{OR}=10.1$ (1.3-76.6) and 82.8% vs. 68.6, $p=0.041$ , $\text{OR}=2.2$ (1-4.7), respectively. Patients with AIRE rs2075876 A alleles had a higher damage index ( 1 ± 1.3 vs. 0.6 ± 1.1, $p=0.045$ ) while the LSI was greater in patients with AIRE rs2075876 (8.5 ± 0.5 vs. 7.8 ± 1.3, $p=0.002$ ) and rs760426 (8.6 ± 11 vs. 7.8 ± 1.2, $p=0.031$ ) under the recessive models. Conclusion. AIRE rs760426 could share in SLE susceptibility while AIRE rs2075876 could influence the disease expression and burden in Egyptian patients.