NPHS2 gene sequencing results in children of the Azerbaijani population with different types of nephrotic syndrome caused by chronic glomerulonephritis.

Abstract

The aim of the study was to determine the mutation of the podocin gene (NPHS2) in children with minimal changes diseases (steroid sensitive nephrotic syndrome (NS)) and steroid resistant NS. Despite the fact that the role of genetic factors is a well-known phenomenon, in NS there are still unknown aspects that are yet to be discovered. NS, type 2 is caused by NPHS2 gene and is characterised with proteinuria, minimal change disease on renal biopsy, poor response to steroid treatment, etc.METHODS: Twenty-nine children (65.5 % male, 34.5 % female) with nephrotic syndrome caused by chronic glomerulonephritis were examined and patients were tested for NPHS2 gene with Sanger technique. The average age was 7.2 ± 2.65 years. 82.8 % of patients had NS with minimal changes, 17.2 % had a steroid resistant NS. The analysis of the NPHS2 gene revealed a likely pathogenic (Arg168His), uncertain significance (Pro20Ley, Leu169Pro, Val180Met, Arg229Gln, Val290Met) and benign (Gly34Gly, Ala318Ala) variants. No novel variants were detected. This is the first study investigating the nephrotic syndrome related to NPHS2 gene in Azerbaijani population. The high prevalence of uncertain significance variants emphasises the importance of population studies in this region as such data are necessary for classifications of the detected genetic variants (Tab. 1, Ref. 25).