Relationship between γ-interferon gene polymorphisms and susceptibility to brucellosis infection

• Published in: Microbiology and immunology 2013-11, Vol.57 (11), p.785-791
• Main Authors: Eskandari-Nasab, Ebrahim, Moghadampour, Mehdi, Hasani, Seyed-Shahaboddin, Hadadi-fishani, Mehdi, Mirghanizadeh-Bafghi, Seyyed-Ali, Asadi-Saghandi, Abolghasem, Zare, Fateme, Sadeghi-Kalani, Behrooz, Ghazali-bina, Mehran
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Brucella - physiology; Brucellosis; Brucellosis - genetics; Brucellosis - microbiology; Case-Control Studies; Child; European Continental Ancestry Group - genetics; Female; gene polymorphism; Genetic Predisposition to Disease; Genotype; Humans; interferon-gamma; Interferon-gamma - genetics; Iran; Male; Middle Aged; Polymorphism, Single Nucleotide; Young Adult
• ISSN: 0385-5600; 1348-0421
• DOI: 10.1111/1348-0421.12093

ABSTRACT Interferon‐gamma (IFN‐γ) is a pro‐inflammatory cytokine that plays a pivotal role in the defense mechanism against Brucella infection. It was hypothesized that the IFN‐γ in (+874 A/T in intron 1) TT and +5644 T/A, TT genotypes, which are reportedly associated with high IFN production, are associated with susceptibility to brucellosis in Iranian subjects. Genotyping of these IFN‐γ variants by an allele‐specific polymerase chain reaction method was performed in 281 subjects, comprising 153 patients with active brucellosis and 128 healthy controls. It was found that the +874 minor allele (A) and homozygote genotype (AA) were significantly more frequently present in brucellosis patients than in controls (OR = 2.588; 95% CI, 1.313–5.104; P = 0.006 for the AA genotype; OR = 1.575; 95% CI, 1.124–2.216; P = 0.010 for the A allele). However, the allelic and genotypic distribution of the IFN‐γ polymorphism at position UTR5644 A>T did not differ significantly between patients and controls (P > 0.05). The distribution of haplotypes in this study suggests that the T/A haplotype (+874/UTR5644), which was present more frequently in controls than in patients, may protect subjects against Brucella infection. It is suggested that IFN‐γ +874 AA genotype and A allele are risk factors for developing brucellosis infection in Iranian subjects.