Association of HLA DRB1 alleles with juvenile idiopathic arthritis in Mexicans.

Objective: The aim of the study was to investigate association between HLA class II alleles and juvenile idiopathic arthritis (JIA) in Mexican patients.

Patients And Methods: We typed 120 patients with JIA and 99 healthy controls for HLA class II alleles were performed by PCR-SSO. Differences between the whole group of JIA and its subtypes and controls were calculated by using the Xi2; p-values were corrected (pc) with Bonferroni's test.

Results: The alleles HLA-DRB1*01 (pc= 0.00083) and HLA-DRB1*04 (pc=0.0049) were strongly associated with systemic JIA, while HLA-DRB1*11 and HLA-DRB1*14 were found to have decreased frequencies in the patients with systemic JIA compared to the controls. Two alleles were found to have increased frequencies with JIA oligoarthritis subgroup, HLA-DRB1*11 (p=0.01, pc=NS) and HLA-DRB1*13 (p=0.01, pc=NS). The HLA-DRB1*04 was found increased frequencies with susceptibility for RF negative and RF positive polyarthritis JIA subgroups (p correction resulted in loss of significance). In contrast two alleles HLA-DRB1*07 and HLA-DRB1*14 were found decreased frequencies only patients RF positive polyarthritis JIA subgroup compared to the controls (pc=NS).

Conclusion: The profile of HLA-DRB1 alleles associations in Mexican with JIA were somewhat distinct from association typically found in Caucasians.