Abstract
Purpose::
Single nucleotide polymorphisms (SNPs) in cytokine genes can predispose to immune mediated diseases and can also affect the phenotype of the disease. The aim of this study was to see whether SNPs in Th1 cytokines IL-12, IL-18 & TNF-α or in Th2 cytokines IL-10 and IL-4 can predict genetic susceptibility in patients with non-infectious posterior segment uveitis (PSU).
Methods::
176 Caucasian patients with PSU and 271 ethnically matched controls were genotyped for IL-12 1188A/C, IL-18 -137G/C, IL-18 -607C/A, TNF -238G/A, TNF -308G/A, TNF -857C/T, IL-10 -592C/A, IL-10 -1082G/A & IL-4 -590T/C SNPs. The genotyping was performed using TaqMan® 5' nuclease assay and statistical analysis was performed SPSS V13.0 using multiple logistic regression method.
Results::
The frequency of IL-18 -137 CC was significantly higher in PSU compared to controls (p=0.009, pc=0.01). However subgroup analysis revealed that this IL-18 -137C allele was strongly associated with the presence of retinal vasculitis (p=0.000002). The A allele at position -607 of IL-18 was also associated with retinal vasculitis (p=0.000008) and so was the IL-12 1188 C allele (p=0.0004). It was also noted that the 592C and 1082G alleles of IL-10 gene that decrease IL-10 expression an thus enhance Th1 response were associated with poor visual outcome (p=0.006)
Conclusions::
Polymorphisms in IL-12 and IL-18 genes can be a predictor of vasculitis in patients with PSU
Keywords: uvea • cytokines/chemokines • genetics