Clinical use of the VNtyper-Kestrel pipeline for MUC1 variant detection in autosomal-dominant tubulointerstitial kidney disease.

backgroundAutosomal-dominant tubulointerstitial kidney disease caused by MUC1 (ADTKD-MUC1) is a rare disorder characterized by progressive kidney dysfunction. Pathogenic variants in MUC1 are difficult to detect owing to the variable number tandem repeat region. To address this issue, VNtyper-Kestrel, a bioinformatics pipeline for short-read sequencing data, was recently developed. In this study, the performance of VNtyper-Kestrel for detecting MUC1 variants in clinical settings was evaluated.

methodsWe used VNtyper-Kestrel to retrospectively analyze short-read sequencing data for 209 individuals with suspected ADTKD who were previously evaluated through long-read sequencing. Data from a panel including ~ 180 genes and an ADTKD-specific panel were used. In addition, the pipeline was applied to 976 patients with suspected hereditary kidney diseases other than ADTKD and positive cases were validated using long-read sequencing. Accuracy was assessed by comparisons with the results of long-read sequencing.

resultsUsing VNtyper-Kestrel, we identified MUC1 variants in 16 of 19 confirmed cases of ADTKD-MUC1. Three initially negative cases were reanalyzed using the ADTKD-specific panel, yielding positive detection results with high confidence. We obtained two low-confidence positive results from 190 cases of suspected ADTKD and 10 low-confidence positive results among 976 non-ADTKD cases; however, all were classified as false positives upon long-read sequencing validation.

conclusionsVNtyper-Kestrel demonstrated high sensitivity in identifying MUC1 variants when sequencing coverage was adequate, supporting its potential as a rapid and cost-effective screening tool. However, confirmatory long-read sequencing is needed in uncertain cases. Optimizing coverage and refining patient selection criteria could improve the clinical utility of this approach.