Blindness due to retinal degeneration affects millions of people worldwide, but many disease-causing mutations remain unknown. PNPLA6 encodes the patatin-like phospholipase domain containing protein 6, also known as neuropathy target esterase (NTE), which is the target of toxic organophosphates that induce human paralysis due to severe axonopathy of large neurons. Mutations in PNPLA6 also cause human spastic paraplegia characterized by motor neuron degeneration. Here we identify PNPLA6 mutations in childhood blindness in seven families with retinal degeneration, including Leber congenital amaurosis and Oliver McFarlane syndrome. PNPLA6 localizes mostly at the inner segment plasma membrane in photoreceptors and mutations in Drosophila PNPLA6 lead to photoreceptor cell death. We also report that lysophosphatidylcholine and lysophosphatidic acid levels are elevated in mutant Drosophila. These findings show a role for PNPLA6 in photoreceptor survival and identify phospholipid metabolism as a potential therapeutic target for some forms of blindness.

AUTOSOMAL dominant optic atrophy (Mendelian Inheritance in Man 165500 ¹) is a hereditary disorder characterized by bilateral insidious onset of vision loss, dyschromatopsia, central visual field defects, and optic nerve pallor.^2-5 The gene is highly penetrant and has variable expressivity.

Autoimmune retinopathy (AIR) is a rare and still poorly understood immune-mediated disease that may cause inflammation from circulating autoantibodies against the retina. It may be related to history of autoimmune disease in the patient or in a family member or the presence of neoplastic disease in the individual. The disease may be subdivided into paraneoplastic and non-paraneoplastic AIR. When related to melanoma, it is referred to as MAR, and when related to other cancers, it is called CAR. The exact prevalence of AIR is unknown. It mainly affects older adults. Patients present with bilateral and asymmetric scotomas, photopsias, visual field defects, with rapidly progressive visual loss in late onset. In the initial stage, fundus examination is unremarkable, and in late stages, there is limited retinal epitheliopathy and vascular attenuation, with or without optic disc pallor, associated or not with intraocular inflammation and with no evidence of degenerative retinal disease. A clinical investigation with detailed anamnesis and laboratory tests should be performed to search for an associated neoplasm. Ophthalmologic and complementary examinations such as full-field electroretinogram, optical coherence tomography, visual field and fundus autofluorescence, help the diagnosis. Blood tests to search for autoantibodies should be requested. Management consists of prolonged immunosuppression, which may be combined with antioxidant vitamins. In general, the prognosis is uncertain, so the disease still needs to be better understood. More studies should be performed to improve diagnostic measures and define specific management that could preserve or even restore vision.