Analysis of HLADRB1 Allels and DRB1 *01,*04,*07,*08 and *10 subtypes in patients with rheumatoid arthritis

Introduction and Aim: Rheumatoid arthritis (RA) is a complex disorder that has a genetic component. Although associations of RA and HLA have previously been investigated in various populations studies in Turkish population are very limited. Determining the frequency of HLA-DRB1 and its some sub-groups (HLA-DRB1*01, *04, *07, *08, *10) in patients with RA, and their associations with the functional stage and seropositivity of the disease have been aimed in this study.Material and Methods: Among the admissons to Dicle University School of Medicine Physical Therapy and Rehabilitation Outpatient Clinic a total of 96 (78 female, 18 male) patients who were diagnosed with RA according to the 1987 American Collage of Rheumatology (ACR) criteria with the mean age of 46.97 ±13.44 years and 84 (36 male, 48 female) healthy control subjects with the mean age of 29.77± 16.99 years have been introduced to the study. All participants were evaluated in terms of clinical and laboratory parameters. HLA-DRB1 genotyping have been carried up by using PCR-SSP HLA-DRB1 Low Resolution gene panel. Subtypes of HLADRB1*01, *04, *07, *08, *10 were identified by PCR-SSP HLA-DRB1 High Resolution gene panel. Functionality and seropositivity of RA patients were also evaluated.Results: In RA patients types which have highest allel frequencies are DRB1*04 (%27.6), DRB1*11 (%14.6), and DRB1*15 (%13.5) in order; whereas, it was DRB1*11 (%24.4), DRB1*04 (%19.6), and DRB1*07 (%14.9) in the control group respectively. When allel frequecies of RA patients and control subjects were compared, the frequency of DRB1*10 allel was found to be higher, and DRB1*07 ve DRB1*11 allel frequencies were found to be significantly lower in RA patients (p<0.05). The comparison of HLADRB1 sub-types between groups showed significantly higher frequencies of DRB1*0401, *0408, and *1001 sub-types (p<0.05), and significantly lower frequencies of DRB1*0402, *0403, and *0701 sub-types in RA patients (p<0.05). There were no statistically significant association between seropositivity and allels and their sub-types (p>0.05). DRB1*10 allel was found to be associated with good functional status (stage 1-2); whereas, DRB1*11 was with poor functional status (stage 3-4) (p<0.05).Conclusions: In RA patients living in our area, DRB1*0401, *0408, *10, and *1001 allels might be associated with increased tendency to the disease; whereas, DRB1*0402, *0403,*0701, and *11 allels with decreased tendency to it. DRB1*10 and DRB1*11 allels may be related with disease severity in RA patients.