hla-dqb1 polymorphisms and juvenile idiopathic arthritis: a case-control association study among iranian children

Background: juvenile idiopathic arthritis (jia) is an important cause of inflammatory arthritis during childhood. hla class ii genes have been recognized as susceptibility factors for jia development. this study aimed to investigate the association between hla-dqb1 allele polymorphisms and jia and its subtypes in a population of iranian children.methods: in this case-control study, hla typing was carried out on 60 children with systemic-onset jia (28 patients) and oligoarticular jia (32 patients) and 50 controls with the same age range for hla-dqb1 alleles. genotyping was performed by polymerase chain reaction using sequence-specific primers (pcr-ssp) and touchdown pcr methods. finally, the sequencing of hla polymorphisms was done.results: there was a significant association among dq2 (dqb1*02:01) (p = 0.028), dq7 (dqb1*03:01, *03:04) (p = 0.046) alleles, and jia. none of the tested alleles demonstrated protective effects. the frequencies of dq7 (dqb1*03:01, *03:04) (p < 0.001) and dq5 (dqb1*05:01- *05:04) (p = 0.03) alleles were significantly higher in patients with oligoarticular jia compared to the control group. in patients with systemic-onset jia, dq2 (dqb1*02:01) subtype also showed a significant association with this disorder's subtype (p < 0.001).conclusion: it was found that distinct polymorphisms in the hla-dqb1 locus could confer susceptibility to jia in iranian children. in this regard, the observed associations between hla-dqb1 and jia would be applicable for developing diagnostic, preventive, and therapeutic approaches.