Functional polymorphism of interferon-γ (IFN-γ) gene +874T/A polymorphism is associated with pulmonary tuberculosis in Zahedan, Southeast Iran.

Concerning the key role of interferon-γ (IFN-γ) in the protective immunity against Mycobacterium tuberculosis, we aimed to find the possible association between single nucleotide polymorphism of IFN-γ +874T/A (rs61923114) and pulmonary tuberculosis (PTB). This case-control study was performed on 142 PTB patients and 166 healthy subjects. Genotype analysis was done using amplification refractory mutation system-PCR (ARMS-PCR). We found that the AA genotype of +874A/T IFN-γ is a risk factor for PTB (OR = 3.333, 95% CI = 1.537-7.236, p=0.002). The results showed that the +874A allele frequency was higher in PTB than in normal subjects (OR = 1.561, 95% CI = 1.134-2.480, p=0.007). In conclusion, significant association was found between the IFN-γ +874T/A polymorphism (rs61923114) and susceptibility to PTB in a sample of Iranian population.