COL4A4 and autosomal dominant polycystic kidney disease: As suggested, a study specifically designed to assess the prevalence of co-occurring pathogenic or likely pathogenic variants in both collagen genes (COL4A3, COL4A4, COL4A5) and ADPKD-related genes (PKD1, PKD2, GANAB, DNAJB11) within the same individuals would be valuable.