HLA antigens and primary osteoarthritis of the hand

Objective. Many studies have examined genetic factors associated with either development or severity of primary osteoarthritis (OA). Analyses of the frequencies of HLA antigens in various OA populations have yielded conflicting results; an increased frequency of HLA-A1, B8, and DR4 alleles has been suggested. We investigated the interrelationship between HLA antigens and primary OA. Methods. We analyzed the frequency of HLA-A, B, C, DR, and DQ antigens in 95 patients (82 women, 13 men) with primary OA of the hands compared to 200 controls matched for age, sex, and ethnicity. Class I and Class II HLA antigens were evaluated using conventional serologic typing. Results. No statistically significant difference in the distribution of HLA-A1 and B8 antigens was observed in patients with OA compared to controls. By contrast, HLA-B35, B40, DQ1, and CW4 antigens were overrepresented in the OA patients. Haplotype analysis showed an association of B35-DQ1, B40-DQ1, and DR2-DQ1 with increased OA risk. Conclusion. Our results suggest a role of the HLA system in the etiopathogenesis of primary OA of the hand.