Editor—Sweet et al investigated the serum transferrin receptor (STfR) and, for the first time in neonates, transferrin receptor-log ferritin (TfR-F) ratio in a prospective series of cord blood taken from term infants and their mothers. They are to be congratulated on completing another piece of the complex jigsaw that is fetal and neonatal iron metabolism.

STfR and TfR-F were increased in iron deficient mothers, but not in their infants. The authors discussed at some length the translational (not transcriptional as stated in the discussion) control of intracellular ferritin synthesis.1 They measured serum ferritin, which is a glycosylated form of L-ferritin, and has been shown to correlate with intracellular iron in …