The human gene SLC39A8 encodes the zinc transporter ZIP8 (BIGM103, BCG-induced integral membrane protein in monocyte clone 103 protein). It is highly expressed in the pancreas and localized to the plasma membrane where it mediates the influx of zinc into the cell (Besecker B et al, 2008). The highly homologous mouse ZIP8 have been shown to play important roles in regulating zinc homeostasis and determining sensitivity to cadmium toxicity in mouse testicular endothelium and kidney tissue. It is expected the human transporter plays a similar role (He L et al, 2009). ZIP8 belongs to the LZT subfamily of ZIP transporters.