Correlation analysis of the HLA-DPB1*05:01 and BTNL2 genes within the histocompatibility complex region with a clinical phenotype of psoriasis vulgaris in the Chinese Han population.

BACKGROUND: The human major histocompatibility complex (MHC) is known to be highly polymorphic and has been identified to be associated with numerous diseases. The HLA-DPB1 and BTNL2 genes were associated with psoriasis for the first time. The present study aims to investigate the relevance of the HLA-DPB1 and BTNL2 genes with respect to clinical phenotypes of psoriasis vulgaris (PV).

METHODS: To investigate whether the HLA-DPB1 and BTNL2 polymorphisms were associated with clinical phenotypes of PV in Chinese Han population, we conducted an analysis in case-controls and case-only subjects (9906 controls and 8744 cases) via MHC targeted sequencing stratified analysis.

RESULTS: In cases and controls, analysis showed that the genotype of HLA-DPB1*05:01 was associated with type of guttate [p = 3.914 × 10-2 , odds ratio (OR = 0.9335)] and northern region (p = 1.182 × 10-3 , OR = 0.9108). In the case-only analysis, the genotype of HLA-DPB1*05:01 was significantly correlated with geographical region (p = 1.36 × 10-3 , OR = 1.134). In cases and controls, analysis showed that the genotype of BTNL2 (rs 41355746) was associated with being male (p = 2.563 × 10-2 , OR = 0.8897), early-onset (p = 9.399 × 10-3 , OR = 0.8856), guttate (p = 2.469 × 10-2 , OR = 0.8558) and family history (p = 1.51 × 10-4 , OR = 0.772). In the case-only analysis, the genotype of BTNL2 (rs41355746) was significantly correlated with family history (p = 1.768 × 10-3 , OR = 0.757) and age of onset (p = 3.818 × 10-2 , OR = 1.195).

CONCLUSIONS: The results of the present study indicate that the HLA-DPB1*05:01 gene was associated with the geographical region of PV and the BTNL2 gene was significantly associated with family history and age of onset of PV. In conclusion, the HLA-DPB1*05:01 and BTNL2 genes might be responsible for the complicacy of clinical features.