RESUMEN
OBJECTIVE: Various cytokine polymorphisms have been associated with genetic risk factors predisposing to Rheumatoid Arthritis (RA) in different populations. To predict the clinical outcome as well as response to therapy in RA, studies aimed to describe genetic markers. The present study aims to search for polymorphisms of 13 cytokine coding genes in the Eastern Black Sea Region of Turkey. METHODS: DNAs of 49 patients and 96 healthy bone marrow and kidney donors were isolated from peripheral blood samples. Genotyping was performed using the Heidelberg Cytokine Typing Tray kit. PCR products were visualized on an agarose gel, and results were analyzed using the interpretation scheme provided with the kit. Arlequin 3.5 software was used for statistical analysis. RESULTS: No positive association was found between allele frequencies and the disease. However, a negative association was found for the IL-A -889 C allele (p=0.02, OR=0.533, Wald's 95% CI=0.318-0.893). IL-12 -1188 CC (p=0.01, OR=3.667, Wald's 95% CI=1.246-10.786), IL-4 -1098 GT (p=0.02, OR=2.405, Wald's 95% CI=1.129-5.125) genotypes were found positively associated with the RA, while IL-4 -590 CT (p=0.02, OR=0.422, Wald's 95% CI=0.201-0.886) was found negatively associated with the disease. In addition, IL-6 GG haplotype was found positively associated with the RA (p=0.02, OR=1.880, Wald's 95% CI=1.086-3.254). CONCLUSION: Our findings suggest that some polymorphisms of the IL-1A, IL-2, IL-4, IL-6 and IL-12 could be responsible for the susceptibility or protective to RA in our study population. Multi-centered and large numbers of subjects containing studies that search for cytokine polymorphisms will gather more information regarding the susceptibility to RA of Turkish patients.
RESUMEN
AIM: The aim of this study was to investigate the associations between human leukocyte antigen (HLA)-DRB1 alleles with genetic susceptibility to rheumatoid arthritis (RA) and production of antibodies against cyclic citrullinated peptide (anti-CCP antibody) and rheumatoid factor (RF) in Turkish RA patients. METHODS: We studied 291 RA patients and 253 controls. Genotyping was performed by polymerase chain reaction with sequence-specific oligonucleotide probes hybridization method. Serum levels of anti-CCP antibody, IgM-RF and high sensitive C-reactive protein titers were measured by commercial kits using immunological methods. RESULTS: We found that HLA-DRB1*04 and *09 alleles were associated in anti-CCP+ and anti-CCP+ RA patients (P < 0.0001 and P < 0.001, respectively), while DRB1*01 and *04 were determined to be higher in RF+ RA patients (P < 0.001 and P < 0.0001, respectively). Moreover, DRB1*11 and DRB1*13 alleles were determined to be lower in RF and anti-CCP/RF+ RA patients (P < 0.001 for both). HLA-DRB1*04 was identified as a common responsible allele for susceptibility to the disease in anti-CCP, RF and anti-CCP/RF- RA patients (P = 0.0018, P = 0.0004 and P = 0.0023, respectively). HLA-DRB1*13 allele alone was found to be protective against to anti-CCP+ and RF- RA (P = 0.0003 and P = 0.006, respectively). On the contrary, there was no protective allele in anti-CCP/RF- RA as well as anti-CCP- RA patients. CONCLUSION: This study indicates that associate and protective HLA-DRB1 allele distributions are different in autoantibody (anti-CCP or RF or anti-CCP/RF)+ RA and autoantibody- RA patients, with exceptions of DRB1*04 and DRB1*13.
Asunto(s)
Artritis Reumatoide/genética , Autoanticuerpos/sangre , Cadenas HLA-DRB1/genética , Péptidos Cíclicos/inmunología , Adulto , Anciano , Artritis Reumatoide/sangre , Artritis Reumatoide/epidemiología , Artritis Reumatoide/inmunología , Biomarcadores/sangre , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Fenotipo , Factor Reumatoide/inmunología , Turquía/epidemiologíaRESUMEN
Rheumatoid arthritis (RA [MIM 180300]) is a complex, polygenic inflammatory autoimmune disease, resulting from interactions between genetic and environmental factors. Some of the RA-associated HLA-DRB1 alleles have shared epitope, but their distribution varies among different racial/ethnic groups. This study was aimed at investigating the distribution of HLA-DRB1 alleles in patients with RA in eastern Black Sea region of Turkey. DNA samples of 320 patients with RA and 360 healthy controls were studied for the determination of HLA-DRB1 allele distribution using PCR-SSP method. The allele frequencies of HLA-DRB1*01, *04, and *09 were higher in patients with RA compared with the controls (P < 0.005, P < 0.0001, and P < 0.01, respectively). On the other hand, in patients with RA, HLA-DRB1*13 allele was lower than the controls (P < 0.001). Of the HLA-DRB1*04 subgroups, *0401 (40.83% vs. 18.75%, P < 0.001) was the most frequent allele in patients with RA, while DRB1*0402 (30.00% vs. 12.50%, P < 0.005) allele in the controls. HLA-DRB1 allele frequencies in the patients with RA and the controls showed Hardy-Weinberg rule compliance. Results of this study indicate that HLA-DRB1*01, *04, and *09 alleles were associated with RA, and HLA-DRB1*13 was protective allele against RA. Among the subgroups of HLA-DRB1*04, *0401 was detected to be RA associated, while *0402 was being protective. These results have some differences compared with previous reports originating from other regions of Turkey.