Hepatic hepcidin mRNA expression. Hepcidin mRNA expression was measured in age- and sex-matched C57BL/6, Hfe^−/−, and Hfe^VillinCre mice by quantitative real-time PCR using primers that specifically amplify both murine hepcidin isoforms. Groups of male (m) and female (f) mice are represented separately. Mean hepcidin mRNA expression in C57BL/6 males was arbitrarily set as 1; all other data are expressed in relation to this. There is no statistically significant difference in hepcidin expression between the different mouse genotypes. However, hepcidin mRNA expression differs significantly between male (m) and female (f) mice within each genotype (*P < .05; **P < .005, Student t test). Mean values are represented by horizontal bars.