[NPHS2 Mutation analysis study in children with steroid-resistant nephrotic syndrome]

Area of Science:

• Genetics
• Nephrology
• Molecular Biology

Background:

• Podocin, encoded by the NPHS2 gene, is crucial for glomerular filtration.
• Mutations in NPHS2 are a primary cause of autosomal recessive steroid-resistant nephrotic syndrome (SRNS).

Purpose of the Study:

• To identify NPHS2 mutations in Chilean children diagnosed with SRNS.
• To determine the prevalence of common NPHS2 variants in a healthy Chilean adult population.

Main Methods:

• Direct sequencing of NPHS2 coding exons via PCR amplification in 34 Chilean children with SRNS.
• Screening for identified common variants (p.R229Q, p.A284V) in 233 healthy adults.
• Statistical analysis using the exact Fisher test to compare allele frequencies.

Main Results:

• Pathogenic NPHS2 mutations were identified in 7 (21%) of the pediatric SRNS patients.
• The p.R229Q variant was found in 2.46% of healthy adult volunteers.
• p.R229Q and p.A284V were identified as the most frequent NPHS2 variants in Chilean children with SRNS.

Conclusions:

• p.R229Q and p.A284V are the predominant NPHS2 variants associated with SRNS in Chilean children.
• This study establishes a genetic link for these variants in the Chilean pediatric population.
• A proposed screening strategy involves parallel or sequential testing for p.R229Q and p.A284V in SRNS patients and their families.