Atypical retinitis pigmentosa

Large mtDNA deletions account for most cases of ocular myopathy and Pearson s marrow/pancreas syndrome. Ocular myopathy patients can exhibit a variety of clinical symptoms, from mild chronic progressive external ophthalmoplegia (CPEO) to Kearns-Sayre Syndrome (KSS). These diseases are characterized by an early onset of ophthalmoplegia, atypical retinitis pigmentosa, mitochondrial myopathy, and usually cerebellar syndrome and cardiac conduction abnormalities. More than 120 different mtDNA deletions have been identified from patients tissues. Partial duplications of mtDNA have been detected in ocular myopathy and Pearson s syndrome, however, duplications are much rarer than spontaneous deletions in patients with these conditions. Exactly how partial mtDNA duplications arise is unknown. 

Kearns-Sayre syndrome Onset before 20 years of age, characterized by opthalmoplegia, atypical retinitis pigmentosa, mitochondrial myopathy, and one of the following cardiac conduction defect, cerebellar syndrome, or elevated CSF proteins. Deletion of contiguous segments of tRNA and OXPHOS polypeptides, or duplication mutations consisting of tandemly arranged normal mtDNA and an mtDNA with a deletion mutation. 

Bassen FA, Kornzweig AL (1950) Malformation of the erythrocytes in a case of atypical retinitis pigmentosa. Blood 5 381-387... 

Jampel, R. S., and H. F. Falls Atypical retinitis pigmentosa, acanthrocytosis, and heredo-degenerative neuromuscular disease. Arch. Ophthal. 59, 818 (1958). 

Here the syndrome of familial hypolipidemia observed in two sisters by Hooft et al. (1962) has to be mentioned, which is characterized by extreme low concentrations of all plasma lipid fractions, retarded development, atypical retinitis pigmentosa, erythemato-squamous skin lesions and aminoaciduria. 

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