Hematologic parameters and hepatic iron-related genes expression in Tmprss6^+/− mice. (A) Hb, RBC and MCV as determined using Sysmex KX-21 automated blood cell analyzer (Sysmex). (B) Hepcidin (Hamp), Id1, and transferrin receptor-1 (Tfr1) mRNA levels as quantified by real-time polymerase chain reaction (ABI 7900, Applied Biosystems) from livers dissected and snap-frozen immediately after sacrifice. Hypoxanthine phosphoribosyltransferase 1 (Hprt1) was used to normalize mRNA levels. (C) Serum transferrin saturation (only in 8-week-old animals) calculated as a ratio of serum iron and total iron binding capacity (Randox Laboratories Ltd). Seven to 9 mice for genotype were analyzed. All the animals were maintained in the animal facility of San Raffaele Scientific Institute (Italy) in accordance with the European Union Guidelines. The study was approved by the Institutional Animal Care and Use Committee (IACUC) of our institution. IB indicates iron-balanced (carbonile iron 200 mg/kg, SAFE, Augy, France) diet; ID, iron-deficient diet (SAFE); RBC, red blood cell count (10⁶ cells/μL); Hb, hemoglobin (g/dL); MCV, mean corpuscular volume (fL); and TS, transferrin saturation (%). Gray columns represent wild-type mice; and black columns, Tmprss6^+/− mice. Error bars indicate SD. Exact P values are shown over the columns; unpaired, 1-tailed Student t tests were performed for statistical analysis.