Furthermore, analysis of the published array data supplied by Kautz et al (2008) for iron loaded and iron deficient mouse liver (Data available at the National Center for Biotechnology Information [NCBI] Geo database (Edgar et al, 2002), accession GSE10421) in C57 and DBA strains shows that liver Usf1 mRNA was not iron-regulated in either strain whereas Usf2 mRNA was decreased by iron loading in both strains of mice but also decreased in iron deficiency. The gene discussed is USF1; the disease is nutritional disorder.