Objective: Psoriasis and psoriatic arthritis (PsA) are interrelated disorders. To date, no study has compared the differences of genes between patients with PsA and psoriasis and healthy controls in a Chinese population. We conducted a retrospective study to determine the human leukocyte antigen (HLA) -A, -B, -Cw, -DR, and -DQ alleles in Chinese patients with PsA and psoriasis.
Methods: HLA studies were performed using polymerase chain reaction sequence-specific oligonucleotide (PCR-SSO) genotyping methods in 91 patients with PsA and 80 with psoriasis and 75 controls. Age at disease onset, sex, disease duration, enthesitis, and uveitis were also analyzed.
Results: Among the patients with PsA and psoriasis, the frequency of HLA-B27 was significantly higher in PsA and HLA-A*30, -Cw*06, -DR*07 in psoriasis compared with controls. In contrast, HLA-B*58 was more common in controls than in PsA and psoriasis groups, and the prevalence of HLA-DR*17 was significantly higher in controls than in those with psoriasis. Comparing PsA and psoriasis, the prevalence of HLA-B*27 and HLA-Cw*12 were more common in PsA patients, while the prevalence of HLA-DR*07 was higher in those with psoriasis (p < 0.05). Among PsA patients, the association between HLA-B*27 and axial joint involvement and uveitis was significant (p < 0.05).
Conclusion: Certain HLA alleles are found in Chinese patients with psoriasis (HLA-A*30, -Cw*06, -DR*07) and PsA (HLA-B*27). Psoriasis patients with the HLA-B*27 and/or -Cw*12 may have higher risk of developing PsA. Ours is the first study to assess the genetic role of HLA in patients with psoriasis and PsA in a Chinese population.