Other studies showed patients with classic WFS had worse visual acuity and reduced retinal nerve thickness compared with patients with autosomal dominant WFS-like syndrome.12 WFS1 protein expression was measured in a single patient with neonatal diabetes insipidus (DI) and unilateral optic disc hypoplasia.13 This patient was found to have reduced WFS1 protein expression, but as this was due to a segmental paternal heterodisomy of chromosome 4, it is not clear whether other genetic defects were involved. Here, WFS1 is linked to diabetes insipidus.