Validity of CD4 enhancer gene polymorphism in susceptibility and severity of some Iraqi rheumatoid arthritis patients.

Rheumatoid arthritis is one of the most common systemic autoimmune diseases. The CD4 enhancer and promoter seem to be the major regulatory regions for CD4 transcription in T cells; therefore, the study aimed to investigate the role of CD4 enhancer gene polymorphism in susceptibility and severity of rheumatoid arthritis (RA). Fifty RA Iraqi patients and 50 apparently healthy controls enrolled in this study during May to September 2015 in rheumatology consultation clinic/Baghdad teaching hospital. Genotyping of CD4-10845 gene polymorphism had determined by PCR ? RFLP. Patients with AA genotype of CD4-10845 were significantly (p<0.01) more likely to develop RA and having of A allele was significantly more likely to have sever RA (χ?=9.121, P<0.01).