Study On Association Of HLA Alleles With Psoriasis Vulgaris In Mongol Ethnic Group From Inner Mongolia

Objective: By analyzing the genotype frequencies of HLA-Cw and DRB1alleles ofthe Mongolian patients with psoriasis vulgaris, to research the association between Mongolianpeople with psoriasis vulgaris and HLA-Cw and DRB1alleles，to explore pathogenic genes ofthe psoriasis vulgaris and provide a theoretical basis for psoriasis etiology study. Enrichsusceptibility gene maps of psoriasis by studying the relationship between Mongolianpsoriasis vulgaris and HLA，provide valuable information for future psoriasis research, andset up the theoretical basis in gene level diagnosis, treatments, prognosis assessment andresearch of psoriasis. Methods: This study chose the Mongolian people who are unrelatedand living in Inner Mongolia for more than three generations. We extracted the genomic DNAfrom blood cells, and performed genotype for HLA-Cw,DRB1loci in81patients withpsoriasis vulgaris and100controls by means of polymerase chain reaction withsequence-specific primers technique. Based on the distribution of HLA alleles frequenciesbetween patients and control groups, we use statistical software SPSS13.0χ2to analysis thedifferences of allele frequencies between the two groups. Results: A total of10alleles inHLA-Cw site and12alleles in HLA-DRB1site were detected. According to the frequencydistribution differences between psoriasis group and normal group, these alleles werestatistically analyzed. HLA-Cw*04， Cw*06， DRB1*04å'ŒDRB1*07have significantdifferences. Moreover, the frequencies of HLA-Cw*06and DRB1*07were significantlyincreased in psoriasis patients, whereas HLA-Cw*04and DRB1*04frequency were highlydecreased, when compared to the controls（Pc＜0.05）. In patients without family history andonset age＜40, HLA-Cw*06and DRB1*07allele frequency were significantly higher,while the HLA-Cw*04and DRB1*04were significantly lower than the control group（Pc＜ 0.05）. In patients with positive family history and onset age≥40, only HLA-Cw*06allelefrequency was significantly higher（Pc＜0.05）. The gene frequency of HLA-Cw*04andDRB1*04was significantly decreased and that of Cw*06and DRB1*07was significantlyincreased in patients without psoriasis family history (Pc <0.05), and the frequency ofHLA-Cw*06was significantly increased in patients with a positive family history (Pc <0.05).Conclusion: HLA-Cw*06and DRB1*07may be the susceptibility determinant forMongolian with psoriasis vulgaris in Inner Mongolia, while HLA-Cw*04and DRB1*04maybe protective factors against the psoriasis vulgaris. In psoriasis patients with onset age＜40,HLA-DRB1*07may be the susceptibility gene, while HLA-Cw*04, DRB*04may be theprotective factors. There are some genetic differences between patients with and withoutpsoriasis family history and HLA-Cw*06may be the common genetic basis in both of them.