Abstract
BACKGROUND AND OBJECTIVE: This study aims to elucidate the genetic cause of polycystic kidney disease detected in the proband during the fetal period and progressively worsening, thereby providing a reference for research on pediatric polycystic kidney disease. METHODS: Whole-genome sequencing was performed on the proband and family members to identify pathogenic variants. The candidate variants were validated by Sanger sequencing. Finally, bioinformatics analysis tools were employed to predict and evaluate the pathogenicity. RESULTS: A previously unreported, de novo chromosomal inversion(GRCh38:17:g.36934029_37729559inv) was identified in the proband. This variant disrupts the HNF1B gene structure and causes Renal Cysts and Diabetes Syndrome (RCAD). DISCUSSION: Our study identifies (GRCh38:17:g.36934029_37729559inv) in HNF1B as a pathogenic variant underlying RCAD through gene disruption, expanding its known pathogenic variant spectrum. It highlights the value of whole-genome sequencing in detecting complex structural variants and provides crucial evidence for genetic counseling.