Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 3 3 2004 09 15 115 120 Maryam Izad Mohammad Vodjgani Mohammad Hossein Nicknam Jamshid Lotfi Davood Fathi Ali Akbar Amirzargar 2015 10 01 Interferon- gamma (IFN- γ) is an important immune regulator and inflammatory cytokine which is implicated in the pathogenesis of multiple sclerosis (MS). A single nucleotide polymorphism, T to A, at position +874 in the first intron has previously been shown. This polymorphism is associated with IFN- γ production level. To study the effect of this polymorphism on susceptibility to multiple sclerosis, we screened genomic DNA samples from clinically definite MS patients and their unaffected first-degree relatives as controls, using sequence-specific primers (PCR-SSP). The results indicated that MS patients showed a lower TT (21.2% vs. 30.3%) and higher AA (21.2% vs. 12.1%) genotypes compared to controls, although there were statistically no differences in the IFN- γ genotype distribution between these two groups. Thus, our data indicate that there is no association between IFN- γ +874 polymorphism and MS susceptibility or severity of the disease. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/77 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/77/77