B) Methods: A hospital-based case-control study consisting of 519 patients with mite-sensitized persistent allergic rhinitis (PER) and 447 healthy controls was conducted. Five single nucleotide polymorphisms (SNPs) in VDR and CYP2R1 were selected for genotyping.
C) Results: The CT genotype of rs2228570 in VDR exhibited a significantly decreased risk (adjusted OR = 0.63, 95% CI = 0.41-0.96), while the AA genotype of rs2060793 in CYP2R1 exhibited a significantly increased risk (adjusted OR = 1.80, 95% CI = 1.02-3.16) of PER in the juvenile subgroup (< 18 years old). Both the AG and AG/GG genotypes of rs731236 in VDR exhibited a significantly decreased risk (AG: adjusted OR = 0.43, 95% CI = 0.21-0.89; AG/GG: adjusted OR = 0.46, 95% CI = 0.23-0.94) of PER in the female subgroup. Analysis of the locus-locus interactions of VDR and CYP2R1 revealed two models were statistically significant (P < 0.05).
D) Conclusions: Age and gender may have an impact on the association of three SNPs (rs2228570, rs731236, and rs2060793) in genes of the vitamin D pathway with the risk of mite-sensitized PER in this Han Chinese population. The VDR and CYP2R1 polymorphisms may be involved in genetic interactions in the pathogenesis of allergic rhinitis.