PKHD1 and kidney disorder: While MYC expression was marginally detectable in adult kidneys and a kidney from an infant without kidney disease (Supplementary Figure S4), we observed higher MYC abundance in all kidneys from patients with defined pathogenic variants in PKHD1 (Figure 1A), with the highest MYC levels detected in kidneys from patients with PKHD1 truncating pathogenic variants (Supplementary Table S1), resulting in the loss of FPC-CTD (AR1, AR2, AR3, and AR8) (Figure 1A and Supplementary Figure S4).