Genetic Basis of Nephrotic Syndrome

Abstract

Steroid-resistant nephrotic syndrome (SRNS) is a leading cause of end-stage kidney disease in children. Recent findings from genomic studies suggests that 10-30% of all cases of SRNS are monogenic disease where mutation in a single gene is enough to cause disease. More than 60 single gene causes of SRNS have been reported and virtually all these genes localized to the podocyte the glomerular visceral epithelial cell of the kidney hence the term “podocytopathy.” The mechanisms by which the mutations in these genes will cause disease is not completely known; however, emerging data showed that some of these genetic defects can disrupt the podocyte F-actin cytoskeleton and the slit diaphragm (SD), signalling at the SD, and also unsettle metabolic activities that are vital for the normal function of the podocyte. Findings from genomic studies is also informing better classification of disease, thus rather than relying on taxonomy that depends on therapy response and nonspecific findings on biopsy, childhood nephrotic syndrome can now be stratified into monogenic NS and immune-based NS. A subset of the latter is readily identifiable as circulating factor disease. This clearly defined disease stratification has implications for approach to therapy and prognostication. Future challenges include developing platforms for the utilization of genetic information in clinical decision process and harnessing multi-omics data and other cutting edge molecular platforms to identify new and specific treatment modalities for nephrotic syndrome.