Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029089 (ophthalmoplegia)
 3,338 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have recently identified a point mutation in the mitochondrially encoded tRNA(Leu(UUR)) gene which associates with a combination of type II diabetes mellitus and sensorineural hearing loss in a large pedigree. To extend this finding to other syndromes which exhibit a combination of diabetes mellitus and hearing loss we have sequenced all mitochondrial tRNA genes from two patients with the Wolfram syndrome, a rare congenital disease characterized by diabetes mellitus, deafness, diabetes insipidus and optic atrophy. In each patient, a single different mutation was identified. One is an A to G transition mutation at np 12,308 in tRNA(Leu(CUN)) gene in a region which is highly conserved between species during evolution. This mutation has been described by Lauber et al. (1) as associating with chronic progressive external ophthalmoplegia (CPEO). The other is a C to T transition mutation at np 15,904 in tRNA(Thr) gene. Both mutations are also present in the general population (frequency tRNA(Leu(CUN)) mutation 0.16, tRNA(Thr) mutation 0.015). These findings suggest that evolutionarily conserved regions in mitochondrial tRNA genes can exhibit a significant polymorphism in humans, and that the mutation at np 12,308 in the tRNA(Leu(CUN)) gene is unlikely to be associated with CPEO and Wolfram syndrome.
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PMID:Mutations in mitochondrial tRNA genes: non-linkage with syndromes of Wolfram and chronic progressive external ophthalmoplegia. 154 64

The authors report on one case of Wolfram syndrome, a rare condition, which is characterized by juvenile onset diabetes mellitus, diabetes insipidus, optic atrophy and sensorineural deafness. The findings of this 13-year follow-up show that this patient developed typical neurological complications of long-standing diabetes mellitus as in the common type 1 variant. Moreover, some peculiar signs occurred such as anosmia, ophthalmoplegia interna, and central nystagmus. Since Wolfram syndrome is probably part of a more generalized neurodegenerative disorder, long-term prognosis will depend both upon the severity of chronic diabetic complications and upon the rapidity, by which degeneration of cerebellar, pontine and brain stem structures appear. Prognosis of the cardinal clinical signs is such that optic atrophy, though usually quite rapid in the beginning, generally does not lead to complete blindness. Sensorineural hearing loss progresses very slowly so that deafness might be expected exceptionally only. The hearing deficit in classical diabetics, however, is of retrocochlear origin. Therefore, in Wolfram syndrome, a combined inner-ear and retrocochlear hearing loss may occur.
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PMID:Juvenile onset diabetes mellitus, central diabetes insipidus and optic atrophy (Wolfram syndrome)--neurological findings and prognostic implications. 185 94

Among the various central nervous system (CNS) manifestations of mitochondrial disorders (MIDs), cognitive impairment is increasingly recognized and diagnosed (mitochondrial cognitive dysfunction). Aim of the review was to summarize recent findings concerning the aetiology, pathogenesis, diagnosis and treatment of cognitive decline in MIDs. Among syndromic MIDs due to mitochondrial DNA (mtDNA) mutations, cognitive impairment occurs in patients with mitochondrial encephalopathy, lactic acidosis and stroke-like episodes syndrome, myoclonus epilepsy with ragged-red fibres syndrome, mitochondrial chronic progressive external ophthalmoplegia, Kearns-Sayre syndrome, neuropathy, ataxia and retinitis pigmentosa syndrome and maternally inherited diabetes and deafness. Among syndromic MIDs due to nuclear DNA (nDNA) mutations, cognitive decline has been reported in myo-neuro-gastro-intestinal encephalopathy, mitochondrial recessive ataxia syndrome, spinocerebellar ataxia with encephalopathy, Mohr-Tranebjaerg syndrome, leuko-encephalopathy; brain and spinal cord involvement and lactic acidosis, CMT2, Wolfram syndrome, Wolf-Hirschhorn syndrome and Leigh syndrome. In addition to syndromic MIDs, a large number of non-syndromic MIDs due to mtDNA as well as nDNA mutations have been reported, which present with cognitive impairment as the sole or one among several other CNS manifestations of a MID. Delineation of mitochondrial cognitive impairment from other types of cognitive impairment is essential to guide the optimal management of these patients. Treatment of mitochondrial cognitive impairment is largely limited to symptomatic and supportive measures. Cognitive impairment may be a CNS manifestation of syndromic as well as non-syndromic MIDs. Correct diagnosis of mitochondrial cognitive impairment is a prerequisite for the optimal management of these patients.
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PMID:Cognitive dysfunction in mitochondrial disorders. 2233 39