A single base-pair deletion in the WFS1 gene causes Wolfram syndrome.

Wolfram syndrome is a progressive neurodegenerative disorder also known as DIDMOAD (diabetes insipidus, diabetes mellitus, optic atrophy and deafness). The majority of cases are caused by mutations in the WFS1 gene. WFS1 is located at 4p16.1 and encodes wolframin, a transmembrane endoplasmic reticulum (ER) protein involved in the negative regulation of ER stress signalling. To date, over 120 WFS1 mutations have been described. In this study, we report a consanguineous family with three siblings affected by Wolfram syndrome. A homozygous single base pair deletion (c.877delC, L293fsX303) was found in the WFS1 gene in all three affected siblings.