VDR and asthma: Our previous study clearly revealed that alteration in Vit D metabolism including decline serum Vit D concentration, genetic variations in VDR and VDBP genes, and higher levels of serum VDBP increases the risk of chronic urticaria.22 Therefore, the current study was conducted to evaluate the possible association between VDR BsmI, FokI, VDBP HaeIII SNPs, and also Vit D and VDBP concentrations with asthma susceptibility in a Kurdish population.