The majority of Wolfram syndrome 1 patients have biallelic homozygous or compound heterozygous mutations in the WFS1 gene (Inoue et al., 1998; Hardy et al., 1999; Gomez-Zaera et al., 2001; Khanim et al., 2001; Cryns et al., 2003; Hansen et al., 2005); however, autosomal dominant inherited or de novo mutations in the same gene have also been reported in some individuals (Bespalova et al., 2001; Eiberg et al., 2006; Hogewind et al., 2010; Bonnycastle et al., 2013; De Franco et al., 2017). This evidence concerns the gene WFS1 and Wolfram syndrome.