Associations between vitamin D receptor gene polymorphisms and chronic spontaneous urticaria in Chinese Han population

Introduction: Previous studies found that vitamin D receptor (VDR) Taql, Bsml, Fokl and Apal gene polymorphisms are associated with several inflammatory diseases. However, the relationship between VDR gene polymorphisms and chronic spontaneous urticaria (CSU) is not clear. Aim: The purpose of our study was to explore the relationship between the polymorphism of VDR and the incidence of chronic spontaneous urticaria in the Chinese Han population. Meanwhile, the vitamin D levels in patients with chronic spontaneous urticaria were also detected and the effects of VDR gene polymorphism on vitamin D levels were detected. Material and methods: The genotypes of four VDR polymorphisms (Taql, Bsml, Apal, and Fokl) were studied using allelespecific PCR analysis in 90 CSU patients and 90 healthy controls. Results: Compared to the control group, the mutant allele (C) of Fokl were more common in patients with CSU (57.2% vs. 45%, p = 0.020, odds ratio (OR) = 0.612, 95% confidence interval (CI): 0.403-0.928). We found that serum vitamin D levels were significantly lower in CSU patients than in healthy controls (p = 0.023). However, the effect of VDR gene polymorphism on vitamin D levels was not found in patients of CSU. Conclusions: We first reported the effect of VDR gene Fokl (rs2228570) polymorphism on the incidence of chronic spontaneous urticaria in the Chinese Han population.