Association of HLA-DPA1 and DQA1 genes with PLE in Han and Tibetan males in Qinghai, China

Abstract

Abstract BACKGROUND Polymorphic light eruption (PLE) is the commonest photosensitive disorder, characterized by pruritus, erythematous papules, plaques or blister lesions that occur within hours of exposure to ultraviolet radiation. However, the etiology and pathogenesis of PLE are still uncertain. The current study aims to identify the relationship between HLA and PLE, and analyze the discrepancies between Han and Tibetan males on the association of HLA with PLE. METHODS Polymerase chain reaction sequence-based typing (PCR-SBT) method was used to determine the distribution of HLA-DPA1 and -DQA1 alleles among 62 male patients with PLE (45 Hans and 17 Tibetans) and 66 healthy males (52 Hans and 14 Tibetans) in Qinghai region. RESULTS 4 HLA-DPA1 and 11 HLA-DQA1 genotypes were detected in all samples. The allele frequency of HLA-DPA1*01:03 in healthy Han men was significantly higher than that in healthy Tibetan men (Pc=0.008), while the HLA-DPA1*02:01 was significantly lower than that in Tibetan men (Pc=0.04). The frequency of HLA-DQA1*03:03 allele (OR=2.7891, Pc=0.011) was significantly increased in Han men with PLE compared with Han controls , and HLA-DPA1*01:03 allele (OR=7.217, Pc=0.0076) was significantly increased in Tibetan men with PLE than Tibetan controls, whereas HLA-DPA1*02:01 (OR=0.154, Pc=0.008) allele frequency was highly decreased in Tibetan men with PLE. CONCLUSIONS There were racial differences between Han and Tibetan men in HLA gene polymorphism. The HLA-DQA1*03:03 allele could be a susceptible allele of PLE in Han men, and the HLA-DPA1*01:03 allele could be a susceptible allele of PLE in Tibetan men, while the HLA-DPA1*02:01 allele could be a protective allele in Tibetan men.