Interferon Gamma Polymorphism and Expression Relationship with Severity of Coronary Artery Disease in Golestan, Iran

Background: The Coronary artery disease (CAD) occurs as a result of atherosclerotic
plaque formation. The interferon gamma (IFNγ) as a multifunctional cytokine is
involved in inflammatory processes in atherosclerosis.
Objectives: We investigated the relationship between IFNγ (+874T/A) SNP with CAD.
Moreover, we compared IFNγ mRNA expression in CAD patients and healthy controls.
Patients and Methods: This case-control study with randomized sampling included
300 patients with CAD and 301 normal controls. The SSP-PCR method was used for
genotyping IFNγ (+874T/A) gene polymorphism. Quantitative Real-Time PCR was
performed to measure IFNγ mRNA expression. All data was analyzed by GraphPad
software. The chi-square and ordinal logistic regression tests were used to analyze
differences in genotype frequencies.
Results: In this study, there was a significant association between male genders with
CAD (P < 0.001). There was a significant association between genotype T/T and Allele T
of IFNγ (+874T/A) polymorphism with CAD (P = 0.021 and P = 0.022, respectively). The
inheritance model analysis showed that two copy of allele T is required for increased risk
in CAD (P = 0.031). There was a significant association between the genotype T/T of IFNγ
(+874T/A) polymorphism with CAD patients with double and triple vessel disease (P =
0.030 and P = 0.013, respectively). The IFNγ mRNA level in CAD group was significantly
higher than control group (P = 0.024).
Conclusions: Conclusions: IFNγ gene functional polymorphism can be associated with
incidence and severity of CAD. IFNγ mRNA level was also increased in CAD patients
in comparison with controls. Therefore, IFNγ may play a role in predisposition to CAD.