AbstractObjective(s)Deregulation of the immune system through allied factors and cytokine responses are thought to be important contributors to the pathogenesis of asthma. Vitamin D3 and its nuclear receptor appear to be factors that maybe involved in regulating immune responses during the progression of asthma. The aim of this study was to investigate the association between polymorphisms in intron 8 and exon 9 of the vitamin D receptor (VDR) and this disease.Materials and MethodsThis study was performed on 100 asthmatic patients and 100 healthy controls. PCR-RFLP was performed to examine polymorphisms in intron 8 and exon 9 of VDR gene. ResultsOur results showed a statistically significant difference in the Taq-1 evaluated genotypes of exon 9 of the VDR gene when comparing healthy patients to asthmatic patients. ConclusionBased on our results, it can be concluded that VDR and its functional polymorphisms may play an important role in the pathogenesis of asthma.