The Genetics of Nephrotic Syndrome

Area of Science:

• Pediatric Nephrology
• Genetics
• Molecular Biology

Background:

• Nephrotic syndrome (NS) is a pediatric kidney disease characterized by proteinuria, hypoalbuminemia, and edema.
• It involves dysfunction of the glomerular filtration barrier, comprising endothelial cells, glomerular basement membrane, and podocytes.
• While most cases are steroid-responsive (SSNS), 20% are steroid-resistant (SRNS), risking progressive kidney disease.

Purpose of the Study:

• To review the genetic causes of steroid-resistant nephrotic syndrome (SRNS) in children.
• To highlight the increasing understanding of genetic factors in SRNS over the past 15 years.
• To discuss the importance of identifying genetic etiologies for SRNS in pediatric patients.

Main Methods:

• Review of research on genetic causes of SRNS.
• Analysis of over 30 proteins associated with glomerular filtration barrier function in SRNS.
• Examination of genetic etiology prevalence based on age of presentation.

Main Results:

• Over 30 proteins involved in glomerular filtration barrier function are linked to SRNS.
• Genetic causes are identified in ~70% of infants <3 months and 50% of infants 4-12 months with SRNS.
• Genetic mutations are less likely in older children with SRNS.

Conclusions:

• Identifying the genetic basis of SRNS in children is crucial for accurate diagnosis and prognosis.
• Genetic findings inform family counseling, predict post-transplant recurrence, and guide immunosuppressive therapy.
• Further research into genetic risk factors for both SSNS and SRNS is warranted.