Lack of association of two polymorphisms of IRF5 with Behcet's disease

Purpose: Interferon regulation factor 5 (IRF5) is a member of the IRF family of transcription factors that control the transactivation of type I interferon system-related genes as well as the expression of several other genes involved in immune response. Here, we investigated its association with Behcet's disease (BD) in a well defined group of Chinese Han patients. Methods: A total of 152 unrelated Chinese patients with BD and 149 healthy blood donors were genotyped for IRF5 rs2280714 and rs752637 polymorphisms. Genomic DNA was isolated from peripheral blood mononuclear cells. Genotyping of each single nucleotide polymorphism (SNPs) was performed by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Allele and genotype frequencies of IRF5 rs2280714 and rs752637 polymorphisms were compared between patients and controls using a two-sided chi(2) test. Results: The results showed no significant difference concerning the frequency of the allele of rs2280714 and rs752637 polymorphisms between BD patients and the normal controls (p = 0.647 and p = 0.105, respectively). The frequencies of the genotype of rs2280714 and rs752637 were not different between BD patients and the normal controls (p=0.233 and, p=0.266, respectively). Clinical manifestation stratification analysis did not show any association of IRF5 polymorphisms with BD patients (p > 0.05). Conclusions: Our study revealed that the rs2280714 and rs752637 SNPs were not associated with the susceptibility to BD. There was no association between the two polymorphisms of IRF5 and any extraocular clinical manifestations in BD.