The significantly lower SIC, higher the transferrin saturation and serum iron levels in the Gnpat+/− mice is also similar to the hemochromatosis phenotype observed in Hfe and Tfr2 KO mice, where the KO mice have lower SIC as compared with their WT littermates suggesting increased release of iron from the macrophages as a result of reduced hepcidin levels. This evidence concerns the gene HAMP and hemochromatosis type 1.