en علوم پایه پزشکی Basic Medical Sciences تحقیقی Original article <strong><em>Background and objectives:</em></strong> 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).<br> <strong><em>Methods:</em></strong> A case-control study was performed on 130 RA patients and 128 healthy subjects in the north-east of Iran using restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) technique. &nbsp;<br> <strong><em>Results:</em></strong> 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).<br> <strong><em>Conclusion</em></strong>: 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.<span dir="RTL"></span> FokI,TaqI,Vitamin D receptor,Rheumatoid arthritis,restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR), 20 29 http://goums.ac.ir/jorjanijournal/browse.php?a_code=A-10-563-5&slc_lang=en&sid=1 nafiseh kaviani kavianyn@yahoo.com 10031947532846005921 10031947532846005921 No Department of Biology, Gorgan Branch, Islamic Azad University, Gorgan, Iran yaghoub yazdani yaghoubyazdani59@yahoo.com 10031947532846005922 10031947532846005922 Yes Infectious Diseases Research Center, Golestan University of Medical Sciences, Gorgan, Iran Hadi Bazzazi hadi.bazzazi@gmail.com 10031947532846005923 10031947532846005923 No Department of Medical Laboratory Sciences, Gorgan Branch, Islamic Azad University, Gorgan, Iran