In respect to epigenetic changes, iron deficiency is known to alter key metabolic and epigenetic pathways, particularly of neural cells, including the phosphorylation of proteins involved in iron sequestration, glutamate metabolism, and histone methylation (185–187); also, liver hepcidin expression, as well as the liver BMP-SMAD signaling pathway, is suppressed by microRNA (188, 189); however, no significant differences in circulating microRNAs between iron-deficient and -replete persons have been observed (190), although some seem to participate in iron homeostatic events (191). This evidence concerns the gene HAMP and nutritional disorder.