The Association of Vitamin D Receptor Polymorphisms of FokI and TaqI with Rheumatoid Arthritis in North-East of Iran

Abstract

Background and objectives: Vitamin D receptor (VDR) has been identified as a susceptibility gene for several autoimmune diseases. This study was designed to investigate the association of VDR gene polymorphisms with the susceptibility to rheumatoid arthritis (RA). Methods: A case-control study was performed on 130 RA patients and 128 healthy subjects in the northeast of Iran using restriction fragment length polymorphismpolymerase chain reaction (RFLP-PCR) technique. Results: Our findings suggested a significant association of T allele (p=0.01) of TaqI (rs731236), and f allele (p=0.01) of FokI (rs10735810) genetic variants of the VDR gene with RA susceptibility. These significant associations were also found in the T/T genotype of TaqI (p=0.009), and F/f genotype of FokI (P=0.014). The f-T haplotype was more significantly detected in-patients than in healthy controls (p=0.007). Conclusion: The RA group showed an increase in the f allele and heterozygous F/f genotype and also in the T allele and homozygous T/T and heterozygous T/t genotypes as compared to the control group. Our results demonstrated that polymorphisms of TaqI and FokI in the VDR gene might be involved in the development of RA in an Iranian population.

Association of Vitamin D Metabolism Gene Polymorphisms with Autoimmunity: Evidence in Population Genetic Studies

“…The FokI (rs2228570) F allele and FF genotype were associated with genetic RA susceptibility in three case-control studies [ 124 , 125 , 126 ] and three meta-analyses [ 127 , 128 , 129 ]. In a case-control study in eastern Iran, FokI (rs2228570) Ff genotype (OR = 1.68) compared to FF genotype as well as Ff and ff genotypes (OR = 1.86) were associated with RA in a dominant genetic model [ 130 ]. In a cross-sectional study, the FokI (rs2228570) TT (or ff) genotype was associated with higher clinical disease activity in French and Tunisian RA patients [ 131 ] ( Table S2 ).…”