Loss of tissue iron stores in fsn mice after removal of supplemented iron diet. Tissue iron levels in liver (top) are elevated in fsn and normal adult littermates while on a 2% supplemented iron diet compared with iron stores in mice on a regular diet. Liver tissue iron levels drop significantly in fsn mice after the iron diet is eliminated, whereas normal mice maintain iron overloading. Spleen tissue iron (bottom) in adult fsn mice on a 2% iron-supplemented diet is significantly lower than that found in normal adult littermates. Loss of spleen iron stores is seen for fsn mice when the iron diet is removed, whereas normal mice remain with highly elevated iron in spleen tissue. Error bars indicate SEM.