Association of mycoplasma pneumoniae and (rs9271366) HLA-DRB1gene polymorphism with the immune susceptibility to rheumatoid arthritis

Background: Rheumatoid arthritis (RA) is a chronic, inflammatory disease that affects the immune system. The primary cause of RA is unknown, but there is evidence that genetic and environmental factors also contribute to the development of the disease. Objectives: This study aimed to illustrate the relationship between the RA and Mycoplasma pneumoniae. Materials and Methods: The work was performed on 50 RA patients of various ages, ranging from 25 to 75 years of age, who were treated at the rheumatology clinic of the city of Medical Marjan between February 2022 to October 2022. Blood samples were used for DNA extraction. HLA-DRB1, IL-6 and mycoplasma were detected by enzyme-linked immunosorbent assay (ELISA). Results: The results showed that compared with RA patients not infected with Mycoplasma pneumoniae and healthy subjects, serum IL-6 concentration was significantly increased in RA patients infected with Mycoplasma pneumoniae. The results showed that serum concentrations of HLADRB1 were significantly elevated in RA patients infected with M. pneumoniae compared with RA patients not infected with M. pneumoniae and healthy subjects. Conclusions: In HLA-DRB1 the SNP rs9271366 was significantly associated with RA and G allele represent as dominant pathogenic allele in which the individual that carry GG and AG genotype have more susceptibility to mycoplasma infection than subjects that carry AA genotype (P = 0.036).