ObjectiveBreast cancer (BC) is one of the most common diseases in women globally, with an increasing number of deaths associated with it. Recently the role of polymorphisms in the genes encoding cytokines and immune cells has been demonstrated. This study aimed to evaluate the association of IFN-Ɣ + 874 A/T polymorphism with BC clinical symptoms.ResultsThe study included 88 women with BC and 88 healthy women who had no history of cancer and were matched for age and sex. Allele-specific oligonucleotide-polymerase chain reaction technique was used to investigate the IFN-Ɣ polymorphism. Clinical data were obtained from the patients’ records. Our results showed that the frequencies of genotypes in the BC patients were not significantly different from the control subjects. However, in the patients, the AT genotype was associated with the risk of malignant BC. The age at BC diagnosis was not different in patients with AA and AT genotypes; however, it was significantly earlier in HER2 negative subjects (p = 0.002). Given the higher frequency of AT in malignant BC patients, our results confirm the association of the IFN-Ɣ polymorphism with the disease’s progression to a malignant state.