The Polymorphisms of FcγRIIB Gene in rs1050501 and FcγRIIIA Gene in rs396991 and their association with Systemic Lupus Erythematous Disease Activity Index

Systemic lupus erythematous (SLE) is a chronic disease with unknown etiology which can involve different body organs. Polymorphism in Fcγ receptors have been identified as a genetic susceptibility factor to SLE and other autoimmune diseases. This study aimed to identify FcγRIIB genotype in rs10550501 and FcγRIIIA genotype in rs396991, as well as their association with SLE Disease Activity Index (SLEDAI). Eighty clinically diagnosed patients with SLE based on the American College of Rheumatology (ACR) criteria were included. High-resolution melt-polymerase chain reaction (HRM-PCR) method was used to detect FcγRIIB and FcγRIIIA polymorphism. Disease activity was assessed using SLEDAI. Data were analyzed using SPSS software. Of the eighty patients, 90% were women, and 10% were men. Minimum and maximum SLEDAI scores were 0 and 51, respectively, with a mean of 21.1. Among the patients with SLE, FcγRIIB frequency was 37.5 % for TT genotype and 31.25% for CT and CC genotypes. There was no significant association between FcγRIIB genotype and SLEDAI (P = 0.557). FcγRIIIA frequency was 47.5% for TT, 31.25% for CT, and 21.25 for GG genotype. There was a significant association between FcγRIIIA polymorphism and SLEDAI (P = 0.029). The genotypes in rs1050501 position do not have any effect on SLE disease severity. TG genotype in rs396991 has a protective effect in SLE.