Abstract
Purpose:
To determine whether polymorphisms altering the function or expression of IL17A and IL17F, which is a potent cytokine and a potential contributor to the etiology of dry disease
Methods:
Genomic DNA was extracted from blood samples of unrelated dry eye disease patients (without Sjogren’s syndrome) and Sjogren’s syndrome patients. PCR and direct sequencing were used to screen variations in promoter region and 5’ untranslated region IL17A and IL17F genes. One hundred control individuals without corneal disease were selected from the general population
Results:
We investigated 7 SNPs: 5 in IL17A, namely rs8193036, -307 G>A, rs2275913, rs8193037 and rs3819025, and 2 in IL17F, namely, -1658 T>C and -1436 G>A. Among them, the -307 G>A, rs8193037 and rs2275913 of IL17A gene and -1658 T>C of IL17F gene were significantly different between patients and control groups. The *A allele frequency of the -307 G>A and a allele frequency of rs8193037 of IL17A in dry eye patients were significantly decreased compared with control subjects. The frequency of the *A allele of the rs2275913 SNP was higher in the Sjogren’s disease patients than in the controls (OR: 2.32). In IL17F gene, the frequency of the *C allele of the -1658 T>C in both dry eye patient (vs. dry eye O.R. =1.64; vs. Sjogrens’ O.R. = 1.63).
Conclusions:
The present study showed that the genetic variants in IL17A and IL17F, the -307 G>A, rs8193037 and rs2275913 of IL17A gene and -1658 T>C of IL17F gene, are associated with non-Sjogren and Sjogren DED patients. It is suggested that genetic variations of IL17A and IL17F may act as a potential susceptibility variants in Korean dry eye disease