The essential role of Irp proteins is also highlighted by conditional knockout experiments which have shown that lack of Irp1 and Irp2 in the intestine of mice results in early death at around 4 weeks of age likely due to intestinal malabsorption and dehydration, and lack of Irp1 and Irp2 in hepatocytes causes liver failure and death of animals within 12 days postpartum (Galy et al., 2008, 2010). This evidence concerns the gene IREB2 and liver failure.