Further, mutant mice showed moderate proteinuria (Figure 6a-e), with slightly increased excretion of higher molecular weight proteins in the 150-day-old knockout mice (Figure 6c) compared with healthy controls (Figure 6a, which was in contrast to the severe proteinuria of COL4A3-/- mice with ongoing renal failure (Figure 6d). This evidence concerns the gene COL4A3 and kidney failure.