Our results are in agreement with previous studies displaying the high clinical heterogeneity of WFS1 variants in both heterozygous (Rendtorff et al., 2011) and compound heterozygous patients (Lieber et al., 2012), giving the example of a French diabetic girl harboring the same variant (c.2206G>A, p.Gly736Ser) described in our patient P9 and showing all clinical features of WS, including diabetes, optic atrophy, and neurologic symptoms (Giuliano et al., 2005). This evidence concerns the gene WFS1 and diabetes mellitus.