GC and vitamin D deficiency: Increased incidence of serum vitamin D deficiency in subjects with asthma, and association of the rs11168293 G allele on VDR gene with lower 25(OH)D level, higher blood eosinophil count (% of leukocytes) and the rs7041 A allele on VDBP gene with higher IgE level in atopic asthma, let us suggest that vitamin D and a number of its binding protein and receptor gene polymorphisms are important in pathogenesis of asthma.