Association of variable number tandem repeats polymorphism in the IL-4 gene with end-stage renal disease in children

Abstract

Background: End stage renal disease (ESRD) is a common cause of morbidity and mortality among children. Interleukin 4 is a cytokine that might influence the progression of chronic kidney disease (CKD) to end stage renal disease. There are variable number of tandem repeats (VNTRs) in IL4 gene that could play major roles in genetic predisposition to some diseases. Aim of the study: The purpose of this study is to detect the association of allelic variant in intron 3 VNTR-IL4 gene with the end stage renal disease and if these variants could be considered as risk markers for this disease. Subjects and methods: The study was conducted on fifty-five children with CKD and fifty healthy children served as controls. All participants were genotyped for intron 3 VNTR by Polymerase Chain Reaction. Results: The frequency of intron 3 VNTR-IL4 P1P2 + P2P2 genotypes was significantly higher in ESRD-children than those with P1P1 genotype (88.7% vs. 15.4%, OR 43; 95% CI 13–134, P value < 0.001). Also, the frequency of P2 allele was significantly higher in ESRD-children compared with healthy controls (70.9% vs. 8%, OR 28; 95% CI 12–64, P value < 0.001). Furthermore, a significantly higher frequencies of P1P1 genotype and P1 allele among the control group were demonstrated (84.6% vs. 11.3%, P < 0.001 and 92% vs. 29.1%, P < 0.001, respectively). Conclusion: we concluded that the P2 allele is an allelic variant predisposing to ESRD in children with CKD and it could be considered a risk factor for the development of ESRD. Keywords: VNTR-IL4, ESRD, PCR, Children, Gene polymorphism