Retinal dystrophies caused by mutations in RPE65: assessment of visual functions.

AIMS To characterise the disease in patients with mutations in RPE65. METHODS Individuals from two families were studied clinically. RESULTS 13 and 20 year old compound heterozygote individuals from one family with R234X and 1121delA mutations showed nystagmus, macular dystrophy and low contrasted spots in the fundus. Some heterozygotes had macular drusen. A 40 year old compound heterozygote individual from another family with L22P and H68Y mutations had few bone spicule pigment deposits and macular atrophy. CONCLUSION Compound heterozygote individuals had severe rod-cone dystrophies featuring few pigment deposits in the fundus, pigment epithelium atrophy, and early involvement of the macula, with variations in severity leading to the diagnosis of Leber's congenital amaurosis or retinitis pigmentosa. Macular drusen in heterozygotes carrying a null allele may reflect the decreased capacity in the RPE65 function.