HAMP and hereditary hemochromatosis: We thank McProt Biotechnology Laboratories (http://www.mcprot.co.jp) for the measurement of serum hepcidin-25 levels, Kazusa DNA Research Institute (https://www.kazusa.or.jp) for gene mutation analysis of hereditary hemochromatosis, and Editage (http://www.editage.com) for English language editing.