mRNA expression changes: Hfe disruption versus secondary iron deficiency or iron overload. shown is a comparison of mRNA expression changes induced by Hfe disruption with changes induced by secondary iron deficiency or iron overload within the B6 and D2 strains. Quantification of duodenal (Cybrd1, Slc39a4, and Muc3) or liver (Ftl1, Fpn1, Hmox1, Hamp1, and Hamp2) mRNAs was performed by quantitative real-time PCR on 7-week-old mice fed a diet containing 280 mg Fe/kg (wild-type [WT] controls and Hfe-/- mice), an iron-deficient, or an iron-supplemented diet  for 3 weeks before they were killed. Expression values for each mouse were calculated as described in Materials and methods, and divided by the mean expression in control WT mice of the same genetic background. Error bars denote standard deviations. *P < 0.05, **P < 0.01, and ***P < 0.001.