Impact of Vitamin D Receptor Genotypes on Taiwan Asthma Risk

Vitamin D plays a critical role in regulating immune function. In literature, several studies have indicated that variations in the vitamin D receptor gene (VDR) may be associated with the risk of asthma risk. However, the findings remain inconsistent. The current study aimed to assess the influence of VDR polymorphisms on both asthma risk and severity.

A cohort comprising 453 non-asthmatic healthy controls and 198 asthmatic cases was assembled, and the VDR rs731236, rs1544410, rs2228570, and rs7975232 genotypes were determined utilizing polymerase chain reaction-restriction fragment length polymorphism methodology.

Our findings indicated that people carrying the variant AG and AA genotypes of VDR rs2228570 demonstrated an elevated risk of asthma compared to wild-type GG carriers (odds ratio=1.55 and 2.19, 95% confidence interval=1.02-2.35 and 1.37-3.49; p=0.0507 and 0.0014, respectively). Furthermore, individuals carrying the variant A allele at VDR rs2228570 exhibited a higher risk of asthma than those carrying the wild-type G allele (odds ratio=1.51, 95% confidence interval=1.19-1.92; p=0.0008). Moreover, a significant association was observed between VDR rs2228570 A-carrying genotypes and increased the severity of asthma symptoms among asthmatic patients (p for trend=0.0024).

The variant A allele at VDR rs2228570 was associated with higher asthma susceptibility, and may serve as a predictor for asthma symptom severity. Our findings encouraged further validation in larger and diverse populations to further elucidate the significance of VDR genotype in asthma development.