at&t oklaHoma scHolar

systemic sLE erythematosus is a chronic relapsing autoimmune disease that affects multiple organ systems. studies have shown overproduction of IL-18 in a number of autoimmune and inflammatory diseases. Indeed, serum IL-18 levels in sLE patients correlate with disease activity. Further, IL-18 treatment accelerates autoimmunity in MrL/lpr sLE prone-mice. serum IL-18 levels are also increased in patients with behçet’s disease (bD), a chronic inflammatory disease characterized by recurrent oro-genital ulceration, and uveitis. Previously, a study in a spanish population reported an association between a putative functional genetic variant in the promoter region of IL18 (rs360719) and sLE. We attempted to replicate these results in an independent set of turkish sLE patients and controls. Next we examined if the same IL18 polymorphism is associated with bD in turkish patients. Our sample set consisted of 189 sLE patients, 156 bD patients, and 253 ethnicallymatched normal healthy controls. The rs360719 sNP was genotyped using a taqMan assay. We did not find genetic association between the putative functional IL18 sNP rs360719 and sLE in turkish patients. This is in contrary to the findings in the spanish sample set. These data suggest that the genetic association with IL18 might be limited to specific ethnicities, and perhaps contribute to the inter-ethnic clinical heterogeneity in sLE, rather than a general susceptibility to the disease. We did not find genetic association between rs360719 and susceptibility to bD in turkish patients. A genetic association between another sNP in IL18 (rs1946518; -607 c/A) was reported previously in a samples set of bD from Korea, and we are currently genotyping this sNP in our sample. Furthermore, our lab found another gene that is associated with bD using a GWAs approach (KIAA1529). The function of this gene remains unknown. We have selected 14 tag sNPs to fine-map the genetic effect in KIAA1529. Our preliminary results confirmed this association, and our experiments in this locus are in progress.