Association between vitamin D receptor gene FokI polymorphism and atopic childhood bronchial asthma

Objective: To investigate the association between vitamin D receptor (VDR) gene FokI polymorphism and atopic bronchial asthma in Egyptian children. Material and methods: Polymerase chain reaction-restriction fragment length polymorphism was used to determine VDR gene FokI polymorphism in 180 asthmatic children (atopic, n = 90 and non-atopic, n = 90) and 180 age and gender matched healthy children. Serum levels of total IgE were measured by ELISA. Skin prick test was performed on all patients. Results: The frequency of FF genotype was significantly higher in healthy children (n = 90, 50%) versus asthmatic children (n = 39, 21.7%, χ2 = 5.852, OR = 0.23, 95% CI = 0.07–0.78, p = 0.016). The frequency of FF genotype was significantly higher among healthy children (n = 90, 50%) compared to atopic asthmatic children (n = 12, 13.4%, χ2 = 9.745, OR = 0.11, 95% CI = 0.02–0.46, p = 0.002). Also, its frequency was significantly higher among non-atopic asthmatic children (n = 27, 30%) compared to atopic asthmatic children (n = 12, 13.4%, χ2 = 4.394, OR = 0.21, 95% CI = 0.04–0.94, p = 0.041). Total IgE differed significantly among the three VDR gene FokI polymorphic genotypes in children with atopic asthma (p = 0.007) and the highest median level was detected in ff genotype. Conclusion: Our findings raise the susceptibility of VDR gene to be a candidate gene for atopic childhood bronchial asthma