The Influence of Single Nucleotide Polymorphism of Tumor Necrosis Factor Alpha Gene on The Response to Etanercept in Iraqi Rheumatoid Arthritis Patients

Background: Rheumatoid arthritis (RA) is a chronic autoimmune inflammatory disease that is characterized by the presence of autoantibodies and joint inflammation, which consequently leads to articular cartilage damage. Due to the tumor necrosis factor-alpha (TNF-α) crucial role in the pathogenesis of RA, TNF-α inhibitors have revolutionized this disease treatment.
Objective: To evaluate the influence of the single nucleotide polymorphism (SNP) of TNF-α on the response to etanercept in RA patients.
Methods: The study comprised of 60 RA patients and 25 healthy individuals. The age range of the participants was between 20 and 69 years. DNA sequencing was carried out by using conventional polymerase chain reaction (PCR) and sequencing. The blood samples were taken from the RA patients at the baseline before the administration of anti TNF-α therapy. The level of TNF-α in the sera was measured using an enzyme-linked immunosorbent assay (ELISA).
Results: The TNF-α-308 G/G genotype was the most prevalent in Iraqi RA patients (78%), while there was no significant difference of TNF-α-308 G/A between responders and non-responder group. TNF-α -308 G/G or G/A genotype have no influence on the response to etanercept. The results indicate that the level of TNF-α was significantly different (P <0.05) between RA patients (190.82±12.23 SEM pg/ml) and the control group (106.62± 4.15 SEM pg/ml), while there was no significant difference of the level of TNF-α between responders (188.53 ±15.81 SEM pg/ml) and non-responders (194.25±19.45 SEM pg/ml).
Conclusion: The level of TNF-α was elevated in RA patients in comparison to healthy individuals. The level of TNF-α at baseline have no influence in the response to etanercept in RA patients. TNF-α-308 G/G or G/A gene polymorphism has no influence on the response to etanercept.
Keywords: Rheumatoid arthritis; TNF-α; Etanercept, TNFR, ELISA, PCR.
Citation: Abbas BF, Mohammad NA, Naif HM. The influence of single nucleotide polymorphism of tumor necrosis factor alpha gene on the response to etanercept in Iraqi rheumatoid arthritis patients. Iraqi JMS. 2024; 22(2): 274-282. doi: 10.22578/IJMS.22.2.12