Moreover, a novel CISD2 mutation was discovered recently in a patient with the Wolfram syndrome type 1 classical phenotype, suggesting that type 1 and type 2 Wolfram syndrome could be viewed as a continuous clinical spectrum with overlapping phenotypes, providing a clue that the protein products of WFS1 and CISD2 may reside in the same molecular pathway [24]. This evidence concerns the gene CISD2 and Wolfram syndrome.