In category 1, the following genes were differentially regulated in response to both short- and long-term iron deficiency: up-relulation of G6pc and Sds, genes related to gluconeogenesis, and down-regulation of genes related to fatty acid oxidation, including Hacl1, Bdh2, Dci, Ech and Cyp4a3; the fatty acid biosynthesis gene Acot4; and the oxygen transport genes Hba-a2 and Hbb. The acceleration of the early stages of gluconeogenesis led to increased serum glucose levels in the long-term iron-deficient rats [3]. Here, HBB is linked to Iron deficiency anemia.