A potential regulator of human copper metabolism has recently been described. Copper homeostasis protein cutC homolog (CutC) is a highly conserved cytosolic copper binding protein (Li et al. 2005, Li et al. 2010). Its function in human copper metabolism remains unclear but in C. elegans, the orthologous cutc1 protein down-regulation increases sensitivity to high levels of copper (Calafato et al. 2008).