Uteroglobin gene polymorphism in childhood nephrotic syndrome

Uteroglobin (UG) is a multifunctional protein which can be induced by inhibition of phospholipase A2 and interferes the metabolization of arachidonic acid and also synthesis of prostaglandins and leukotriens. We aimed to investigate the possible role of UG gene polymorphism in children with nephrotic syndrome based on the hypothesis that the increase of inflammatory mediators due to decrease of UG levels with the presence of UG gene G38A polymorphism may play a role in the pathogenesis of glomerular disease.Children (n=136) who were diagnosed as nephrotic syndrome in Gaziantep University Hospital Department of Pediatric Nephrology, and healthy voluntary children(n=70) were included into the study. Children with nephrotic syndrome were divided into two groups as steroid sensitive (n=84) and steroid resistant (n=52) in order to research the relationship between gene polymorphism and steroid response. DNA sample was analysed with PCR-RFLP method to detect the UG G38A gene polymorphism in blood samples of children with nephrotic syndrome and control group.Genotype distrubition of Uteroglobin gene G38A (G/A) was found as AA 12(%14,3), GG 41(%48,8), and AG 31(%36,9) in steroid sensitive group, AA 11(%21,1), GG 20(%38,5), and AG 21(%40,4) in steroid resistant group, AA 4(%5,7), GG 29(%41,4), and AG 37(%52,9) in control group. AA genotype was found to be more common in children with nephrotic syndrome whereas AG genotype was more common in control group. The risk of having nephrotic syndrome was almost 4 fold increased in children with AA genotype (p=0,016, OR=4,09). The risk of having steroid sensitive NS was 3,5 fold increased (p=0,042, OR=3,58) while the risk of having steroid resistant NS was 4,8 fold increased in the same genotype (p=0,014, OR=4,84). We observed that allelic distrubition was not effective either on risk of having nephrotic syndrome, or on steroid response.Further studies evaluating all polymorphisms in larger groups are needed to exactly determine the effect of UG gene G38A polymorhism on development of nephrotic syndrome and steroid response.Key words: Nephrotic syndrome, Polymorphism, Uteroglobin gene