Cytokine gene polymorphisms in Chinese patients with psoriasis
1Department of Dermatology, National Yang-Ming University, Taipei, Taiwan. ytchang@vghtpe.gov.tw
The British Journal of Dermatology
|March 29, 2007
Summary
Genetic variations in the interleukin-12B (IL-12B) gene are linked to psoriasis vulgaris (PV) susceptibility in Taiwanese Chinese. However, HLA-Cw*0602 showed a stronger association, particularly with early-onset PV.
Area of Science:
- Genetics
- Immunology
- Dermatology
Background:
- Cytokine gene polymorphisms are implicated in psoriasis susceptibility.
- Understanding genetic factors is crucial for elucidating psoriasis pathogenesis.
Purpose of the Study:
- To investigate the association between cytokine gene polymorphisms and psoriasis development in Taiwanese Chinese patients.
- To assess the role of specific genetic markers in psoriasis vulgaris (PV) and psoriatic arthritis (PsA).
Main Methods:
- Analyzed DNA from 170 PV patients, 102 PsA patients, and 210 controls using direct sequencing and microsatellite genotyping.
- Examined 28 polymorphisms in 11 cytokine genes (e.g., IL-1, IL-4, IL-10, TNF-alpha).
- Determined genotypes for HLA-Cw*0602, killer cell immunoglobulin-like receptor (KIR) genes, and major histocompatibility complex class I chain-related gene A (MICA) in PsA patients.
Main Results:
- The +4496G allele of the IL-12B gene was more frequent in PV patients (59.4%) compared to controls (49.3%).
- HLA-Cw*0602 allele frequency was significantly higher in early-onset PV patients (25.3%) versus controls (4.8%).
- No significant associations were found for other analyzed cytokine genes, KIR genes, or MICA with PV or PsA, nor with disease onset, gender, or arthritis characteristics.
Conclusions:
- IL-12B gene polymorphism is a risk factor for PV in the Chinese population in Taiwan, though less impactful than HLA-Cw*0602.
- HLA-Cw*0602 is a significant risk factor for early-onset PV.
- Specific polymorphisms in IL-12B and HLA-Cw*0602 are associated with psoriasis susceptibility, while other tested cytokine gene polymorphisms, KIR, and MICA are not strongly linked to PV or PsA in this cohort.
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