Norrie disease (ND) is a rare X linked recessive disorder in which affected males are blind at birth or in early infancy. About one third develop progressive sensorineural deafness. In addition, about 25% of affected males have varying degrees of developmental delay. The ocular findings include bilateral retinal folds, retinal detachment, vitreous haemorrhage, and bilateral retrolental masses consisting of haemorrhagic vascular and glial tissue (vitreoretinal dysplasia).

Histopathological examination of the eyes of an 11 week foetus with ND showed no evidence of primary neuroectodermal maldevelopment of the retina, suggesting that later disordered retinal vascular development may be a more likely disease mechanism.¹

More than 100 different mutations of the ND gene, NDP, have been identified.² Germ line mutations in NDP have also been identified in X linked familial exudative vitreoretinopathy (FEVR) and in retinopathy of prematurity (ROP). Somatic NDP mutations have been implicated in retinal telangiectasis (Coats disease). These findings suggest a …