The prenatal and postnatal development of the eye is determined by complex interactions between a number of genes, their products, and certain environmental factors.1,2 Since each eye is influenced by precisely the same processes as its fellow, mutations in regulatory genes usually lead to symmetric phenotypes. In this report, we describe two siblings of Asian ethnicity, born to unrelated parents with no family history of ocular disease, who have an unusual bilateral retinal dystrophy associated with very asymmetrical ocular growth. Sib 1 was an 8 year old boy with epilepsy who had been born at term after an uneventful pregnancy. Pendular nystagmus had been noted soon after birth and his visual acuity in each eye was 3/60; refraction −17.00 DS right, plano left. Anterior segment examination was unremarkable with normal intraocular pressures. Examination of the right eye (Fig 1A and B) revealed generalised retinal pigment epithelial and …