Objective The vitamin D receptor gene (VDR) polymorphisms and the risk of various infections have been studied. An association with brucellosis and vitamin D levels has been investigated but not yet with VDR gene polymorphisms. We aimed to examine the association between VDR gene polymorphisms and susceptibility to childhood brucellosis.

Methods This case–control study included patients with brucellosis and healthy controls. After extracting genomic DNA using a Qiagen blood DNA isolation kit, five VDR single nucleotide polymorphisms (SNPs), including Cdx-2, FokI, BsmI, ApaI, and TaqI gene, were amplified. Genetic distribution of these SNPs of VDR gene in patient and control groups were compared.

Results A total of 38 patients with brucellosis and 89 healthy controls were evaluated. The genotype distribution of Cdx2, FokI, BsmI, and ApaI polymorphisms were similar between patients and healthy controls. However, the CC homozygous genotype for VDR gene TaqI was significantly overexpressed in patients compared with controls (23.7 vs. 7.9%; p = 0.042). The frequency of the C allele of the TaqI genotype was significantly different between patients and controls (p = 0.018). On the other hand, presence of the A allele in the BsmI was associated considerably with an increased risk of brucellosis (p = 0.037). VDR polymorphism distribution was similar according to age, presence of complicated disease, and presence of bacteremia. The heterozygote TaqI polymorphism was more common in patients presented as subacute and chronic symptoms (p = 0.036).

Conclusion Our results indicated the possible role in TaqI polymorphism of the VDR gene for the risk of brucellosis at the time of exposure to infection.

目的 研究维生素D受体基因（VDR）多态性和各种感染的风险。已经研究了与布鲁氏菌病和维生素 D 水平的关联，但尚未研究与 VDR 基因多态性的关联。我们旨在检查 VDR 基因多态性与儿童布鲁氏菌病易感性之间的关联。

方法 本病例对照研究包括布鲁氏菌病患者和健康对照。使用Qiagen血液DNA分离试剂盒提取基因组DNA后，扩增出5个VDR单核苷酸多态性（SNP），包括Cdx-2、FokI、BsmI、ApaI和TaqI基因。比较了患者组和对照组中 VDR 基因的这些 SNP 的遗传分布。

结果 共评估了38例布鲁氏菌病患者和89例健康对照者。Cdx2、FokI、BsmI和ApaI多态性的基因型分布在患者和健康对照之间相似。然而，与对照组相比，VDR 基因TaqI的 CC 纯合基因型在患者中显着过度表达（23.7 对 7.9%；p  = 0.042）。TaqI基因型的 C 等位基因的频率在患者和对照之间显着不同（p  = 0.018）。另一方面，BsmI 中A 等位基因的存在与布鲁氏菌病风险增加显着相关（p  = 0.037）。VDR 多态性分布根据年龄、复杂疾病的存在和菌血症的存在而相似。杂合子TaqI多态性在表现为亚急性和慢性症状的患者中更为常见 ( p  = 0.036)。

结论 我们的结果表明VDR 基因的TaqI多态性可能在暴露于感染时对布鲁氏菌病的风险起作用。