Weekly issue 2026-W42 ·
Genetic Spectrum and Family-Based Cascade Screening in Vietnamese Families With Autosomal Dominant Polycystic Kidney Disease
Plain language
When a pathogenic gene change causing autosomal dominant polycystic kidney disease (ADPKD) is identified in one person, targeted genetic testing can be offered to family members to see who else carries it. In this cross-sectional study from Vietnam, whole-exome sequencing in 40 unrelated patients with ADPKD found a PKD1 variant in 77.5%, a PKD2 variant in 17.5%, and no ADPKD variant in 5.0%, including nine previously unreported variants. Targeted testing of 89 relatives from families with a confirmed pathogenic or likely pathogenic variant showed that 53 carried the family variant — and about one third of those carriers had no symptoms yet — while none of the 36 relatives without the variant had clinical signs of ADPKD.
Clinical note
Cross-sectional descriptive genetic cohort study (Nephrology (Carlton)). Whole-exome sequencing in n = 40 unrelated Vietnamese probands with clinically diagnosed PKD, followed by Sanger testing in n = 104 relatives (cascade testing in 89 relatives from families with pathogenic/likely pathogenic variants; co-segregation analysis in VUS families). Detected 37 variants (31 PKD1 [83.8%], 6 PKD2 [16.2%]; 9 novel); proband yield was 77.5% PKD1, 17.5% PKD2, 5.0% negative. PKD1 carriers were younger at evaluation than PKD2 carriers (p = 0.029). Among 89 cascade-tested relatives, 53 (59.6%) were variant-positive (34 [64.2%] symptomatic, 19 [35.8%] asymptomatic) and 36 (40.4%) were variant-negative with 0% clinical ADPKD (p < 0.001).
Question for your next visit
Would genetic testing in our family help clarify my diagnosis or help relatives understand their own risk?