A partial overlapping disease, Wolfram syndrome type 2 (WS2), is caused by recessive mutations in the CDGSH Iron Sulfur Domain 2 (CISD2) gene, encoding for a MAM localized protein (also known as Miner1 or ERIS) that, similarly to WFS1, regulates the UPR and calcium homeostasis [249,250,251]. Here, CISD2 is linked to Waardenburg syndrome type 2.