An individualized, stepwise approach with prolonged conservative management may be a reasonable alternative to early bilateral nephrectomies and dialysis in children with CNS and NPHS1 mutations.
Mutations in the NPHS1 gene that encodes nephrin cause congenital nephrotic syndrome (CNS), which is characterized by the loss of the SD and massive proteinuria.
The main objective of this study was to perform the analysis of the NPHS1 gene in patients with congenital nephrotic syndrome in order to determine the molecular cause of the disease.
This study demonstrates that the majority of CNS cases (67%, 8/12 patients) are caused by genetic defects, and the NPHS1 mutation is the most common cause of CNS in Chinese patients.
To date, however, the effect of CNS-associated NPHS1 variants on nephrin phosphorylation remains to be determined, which hampers genotype-phenotype correlations.
In addition, 3D organoid glomeruli from a congenital nephrotic syndrome patient with compound heterozygous NPHS1 mutations reveal reduced protein levels of both NEPHRIN and PODOCIN.
Congenital nephrotic syndrome of the Finnish type (NPHS1) is an autosomal-recessive disorder, characterized by massive proteinuria in utero and nephrosis at birth.
The genetic evaluation revealed a heterozygous variant in NPHS1 (p.Arg207Trp), in NPHS2 (p.Ser95Phe) as well as in PLCE1 (p.Ala1045Ser) and did not explain CNS.
Our study provides further evidence that loss of function of the nephrin gene is the main cause of congenital nephrotic syndrome of the Finnish type in Italian patients.
NPHS1, which encodes nephrin, recently has been identified as the gene in which mutations cause congenital nephrotic syndrome of the Finnish type (CNF).
The prototype of congenital nephrotic syndrome is congenital nephrotic syndrome of Finnish type (CNF, OMIM #602716), which is caused by loss-of-function mutations of the nephrin gene (NPHS1).
Furthermore, we conducted functional analysis of NPHS1 mutations in Japanese patients with congenital nephrotic syndrome using this simple method, which revealed that all pathogenic mutations impaired trafficking to the protein plasma membrane.