Association of VDR gene polymorphisms with risk of relapsing-remitting multiple sclerosis in an Iranian Kurdish population

Abstract

Purpose: The purpose of this study was to evaluate the association of VDR Apa-I, Bsm-I, Fok-I, Taq-I single nucleotide polymorphisms (SNPs) with multiple sclerosis (MS) risk in an Iranian Kurdish population.

Materials and methods: A population including of 118 patients and 124 healthy matched controls were recruited to the study. Genotyping of the SNPs was accomplished using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: The frequency of allele T of Fok-I (P = 0.003) and allele C of Taq-I (P = 0.0003) was significantly different between case and control subjects and showed significant association with risk of MS (OR = 1.84, 95% CI = 1.23-2.76; OR = 1.98, 95% CI = 1.36-2.87, respectively). CT genotype (OR = 1.7, 95% CI = 1.05-2.99) of Fok-I and CC genotype (OR = 2.18, 95% CI = 1.05-4.52) of Taq-I showed a predisposing effect. Combined TT+TC vs. CC for Fok-I (OR = 2.15, 95% = CI 1.29-3.60) and combined CC+TC vs. TT for Taq-I (OR = 2.58, 95% CI 1.51-4.40) were susceptibility genotypes for MS. Apa-I and Bsm-I were not significantly associated with risk of MS (OR < 1, P > 0.05) and any genotypes in any genetic models were not significantly different between cases and controls (P > 0.05).

Conclusion: As a result, Fok-I and Taq-I showed significant association with risk of MS, while Apa-I and Bsm-I were not observed to be related to the risk of the disease in this population.

Keywords: Kurdish population; Multiple sclerosis; association study; single nucleotide polymorphism; vitamin D receptor.