Condition	Features	Genes implicated
RP
X-linked	Early onset Night blindness, progressive VF constriction and loss of vision Least common but most severe	Xp11.3 (RP2) Xp21 (RP3)
Autosomal dominant	Most common and best prognosis	Rhodopsin gene at 3q Peripherin gene at 6p
Lebers congenital amaurosis	An autosomal recessive form of RP	Null mutations in guanylate cyclase or homozygous defects of RPE 65 (this protein influences 11-cis-retinol formation)
Choroideraemia	Childhood onset Night blindness and later loss of vision Granular pigmentary changes initially, then choroidal atrophy later. Patchy non progressive equatorial pigmentary changes	Xq21 locus: deletion to Rab1 gene X-linked recessive
Norrie’s disease	Males affected from birth With bilateral congenital blindness Retinal dysplasia Retinal vascular changes Retinal detachment CataractDeafness and LD	Xp11.1 Xp11.3
Achromatopsia		Homozygous (?recessive) defect in the cone cGMP-gated channel alpha subunit
Red-green colour blindness		X-linked recessive
Blue-cone monochromatism		X-linked recessive
Retinoschisis		X-linked
Albinism	Poor VA and nystagmus in children
Oculocutaneous	Tyrosinase positive group Tyrosinase negative group (severe disease): profound visual loss, photophobia, nystagmusIris transillumination, absent fundal pigmentation, absent foveal reflex Most optic nerve fibres cross at the chiasma (VEP abnormalities see above)	Autosomal recessive
OcularAka Nettleship-Falls albinism	Most hypopigmentation confined to the ocular structures Giant melanosomes in the RPE, iris translucency, strabismus, nystagmus	X-linked recessive
Leber’s hereditary optic neuropathy	Males affected more than females Hyperaemic disc swelling Peripapillary telangiectasia Optic atrophy and optic nerve demyelination Visual failure: the papillomacular bundle is most severely affected	Suspected mitochondrial inheritance since males cannot transmit (although this does not explain the male predominance) Involves an NADH dehydrogenase typically
Kearns-Sayre syndrome	Pigmentary retinopathy Progressive myopathy including cardiac muscle Progressive external ophthalmoplegia	Mitochondrial inheritance Multiple point mutations
Chronic progressive external ophthalmoplegia	Ptosis, myopathy, depression, cataract, ketoacidosis	Mitochondrial or autosomal dominant inheritance (occasionally spontaneous de novo mutation)
Stargardt’s disease	Mild defects cause macular degeneration, intermediate defects cause cone-rod dystrophy, severe defects cause RP	Autosomal recessive. Defects in the ATP-binding cassette (ABCA4) transporter (see above, Rim proteins). Chromosome 1p abnormality
Goldmann-Favre disease	Optically empty vitreous Hyperopia	Autosomal recessive
Homocystinuria		Autosomal recessive
Familial ectopia lentis		Autosomal recessive
Macular corneal dystrophy	Least common but most severe of major stromal corneal dystrophies Grey-white opacities in stroma extending to periphery without clear spaces between	Autosomal recessive
Aniridia		Autosomal dominant (1/3rd are sporadic). Deletions of PAX-6 on chromosome 11
Best disease (vitelliform dystrophy)	Macular degeneration involving the entire RPE layer but only damaging the macula	Autosomal dominant. Heterozygous missense mutations of the bestrophin gene (BEST1) and PRPH2 (peripherin 2) gene
Ehler-Danlo’s syndrome		Autosomal dominant
Stickler’s syndrome	High myopia Retinal detachment	Autosomal dominant (variable expressivity) 60% of patients have a mutation in the COL2A1 gene
Marfan’s syndrome		Autosomal dominant: fibrillin gene on chromosome 15
Myotonic dystrophy	1 in 20,000 Expressionless face Frontal balding Gonadal atrophy Myotonia Cataracts Pigmentary retinopathy Cardiac arrhythmias	Autosomal dominant Chromosome 19 loci Triplet expansion: demonstrates anticipation. Congenital MD is most severe
NF-1	Neurofibromas, optic nerve glioma	Autosomal dominant Chromosome 17q
NF-2	Acoustic neuromas, gliomas, meningiomas	Autosomal dominant Chromosome 22q
Von Hippel-Lindau	Retinal angiomata Cerebellar haemangioblastoma	Autosomal dominant Chromosome 3 (VHL gene)
Tuberous sclerosis	Fundal astrocytomas	Autosomal dominant Chromosome 9q and 16p (TSC1 and TSC2 genes)
Gorlin-Goltz syndrome	Early development of multiple BCCs. Benign jaw tumours, rib and vertebral abnormalities, intracranial calcification, ovarian and cardiac fibromas	Autosomal dominant Chromosome 9 PTCH1 gene: produces patched-1 protein which interacts with sonic hedgehog during development
Retinoblastoma		13q14 (chromosome 13) Appears autosomal dominant but both alleles need to be affected Majority of bilateral and unilateral cases are actually sporadic
Turner’s syndrome	Short stature Hypertension Eyelid pigmentation Epicanthic folds Cataract Ptosis Strabismus Nystagmus	45, X0 Non-dysjunction is usually paternal (ie. occurs in the spermatozoon)
Klinefelter’s syndrome	Tall Bilateral gynaecomastia (breast ca risk) Infertility, hypogonadism	Non-dysjunction during meiosis I47 XXY 47 XXXYY 47, XXYY