The Allelic and Polymorphism Association of Tumor Necrosis Factor-alpha Gene (-308 G/A Genotype) in Some Iraqi Rheumatoid Arthritis Patients

This study aims to determine whether -308 G/A polymorphism in tumor necrosis factor-alpha gene (TNF-?), is associated with susceptibility to rheumatoid arthritis in Iraqi population of TNF-a. This case-controlled study was performed including 42 RA patients (15 males, 27 females; mean age 55,67years; range 30 to 72 years) and 30 healthy controls (10 males, 20 females; mean age 52,8 years; range 30 to 70 years). We determined the frequency of -308 G/A TNF-a gene polymorphism by amplification refractory mutation system-polymerase chain reaction restriction fragment length polymorphism (ARMS-PCR). Also, we determined the association of TNF-? -308 G/A polymorphism with rheumatoid arthritis in Iraqi patients. There wassignificant difference between genotype frequency of -308 G/A polymorphism and rheumatoid arthritis. In RA patients, the genotype frequency of -308 G/Apolymorphism was GG (11.90%), GA (45.24%), and AA (42.86%). In the control group, the genotype frequency of -308 G/A polymorphism was GG (3.33%),GA (83.33%), and AA (13.33%). Statistical analysis showed significant association in the genotype frequency of this AA polymorphism in RA patients (p<0.009*), and GG genotype bot no significant (p=0.390). There was significant difference in genotype frequency of this GA polymorphism in control (p<0.001*). Our findings demonstrate that the TNF-?-308 G/A gene polymorphism may represent a significant risk factor for rheumatoid arthritis in Iraqi population and there is association between the TNF-?-308 G/A polymorphism and rheumatoid arthritis patients