COL4A3 and Renal insufficiency: Systemic deletion of Col4a3 (CMV-Crepos; Col4a3L/L) phenocopied the total body knock out of Col4a3 (Col4a3KO) (Cosgrove et al, 2007; LeBleu et al, 2009), demonstrating a median survival of 28.1 wk and death due to renal failure (Figs 1E and S2A).