Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Since the early days of mitochondrial medicine, it has been clear that optic atrophy is a very common and sometimes the singular pathological feature in mitochondrial disorders. The first point mutation of mitochondrial DNA (mtDNA) associated with the maternally inherited blinding disorder, Leber's hereditary optic neuropathy (LHON), was recognized in 1988. In 2000, the other blinding disorder, dominant optic atrophy (DOA) Kjer type, was found associated with mutations in the nuclear gene OPA1 that encodes a mitochondrial protein. Besides these two non-syndromic optic neuropathies, optic atrophy is a prominent feature in many other neurodegenerative diseases that are now recognized as due to primary mitochondrial dysfunction. We will consider mtDNA based syndromes such as LHON/dystonia/Mitochondrial Encephalomyopahty Lactic Acidosis Stroke-like (MELAS)/Leigh overlapping syndrome, or nuclear based diseases such as Friedreich ataxia (mutations in FXN gene), deafness-dystonia-optic atrophy (Mohr-Tranebjerg) syndrome (mutations in TIMM8A), complicated hereditary spastic paraplegia (mutations in SPG7), DOA "plus" syndromes (mutations in OPA1), Charcot-Marie-Tooth type 2A (CMT2A) with optic atrophy or hereditary motor and sensory neuropathy type VI (HMSN VI) (mutations in MFN2), and Costeff syndrome and DOA with cataract (mutations in OPA3). Thus, genetic errors in both nuclear and mitochondrial genomes often lead to retinal ganglion cell death, a specific target for mitochondrial mediated neurodegeneration. Many mechanisms have been studied and proposed as the bases for the pathogenesis of mitochondrial optic neuropathies including bioenergetic failure, oxidative stress, glutamate toxicity, abnormal mitochondrial dynamics and axonal transport, and susceptibility to apoptosis.
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PMID:Retinal ganglion cell neurodegeneration in mitochondrial inherited disorders. 1926 52

Mutations in the Dynamin 2 gene (DNM2) cause autosomal dominant centronuclear myopathy or autosomal dominant (AD) Charcot-Marie-Tooth (CMT) disease. Here the authors report one large Czech family with 15 members affected with an AD CMT phenotype of extraordinary variability. Genetic linkage analysis using SNP arrays revealed a locus of about 9.6 Mb on chromosome 19p13.1-13.2. In this critical interval, 373 genes were located. The only gene herein known to be associated with an intermediate type of CMT was Dynamin 2 (DNM2). Subsequent sequence analysis of the DNM2 gene in the index patient revealed a novel missense mutation p.Met580Thr. This missense mutation segregated with the neuropathy, indicating the causal character of this mutation. The phenotype of CMT in this family shows mild to moderate impairment with relatively preserved upper limbs and a very broad range of the onset of clinical symptoms from an early onset around the age of 12 to the late onset during the fifth decade. Electrophysiology showed an intermediate type of peripheral neuropathy. The motor median nerve conduction velocity varied from 36 m/s to normal values with signs of asymmetrical affection of peripheral nerves. No additional symptoms such as cranial nerve involvement, cataract, and signs of neutropenia or myopathy syndrome were observed in any member of the family yet. The progression was slow with no loss of ambulation. The authors suggest that the characterization of clinical variability in a single family may help to direct the genetic analysis directly to the rarely observed DNM2 mutations.
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PMID:Phenotypic variability in a large Czech family with a dynamin 2-associated Charcot-Marie-Tooth neuropathy. 2209 29

PHARC (Polyneuropathy, Hearing loss, Ataxia, Retinitis pigmentosa and Cataracts) (MIM# 612674) is an autosomal recessive neurodegenerative disease caused by mutations in the ABHD12 gene. We evaluated two Spanish siblings affected with pes cavus, sensorimotor neuropathy, hearing loss, retinitis pigmentosa and juvenile cataracts in whom the genetic test of ABHD12 revealed a novel homozygous frameshift mutation, c.211_223del (p.Arg71Tyrfs*26). The earliest clinical manifestation in these patients was a demyelinating neuropathy manifested with a Charcot-Marie-Tooth phenotype over three decades. Progressive hearing loss, cataracts and retinitis pigmentosa appeared after the age of 30. We herein describe the complete clinical picture of these two patients, and focus particularly on neuropathy characteristics. This study supports the fact that although PHARC is rare, its phenotype is very characteristic and we should include its study in patients affected with demyelinating polyneuropathy, hearing loss and retinopathy.
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PMID:Phenotypical features of two patients diagnosed with PHARC syndrome and carriers of a new homozygous mutation in the ABHD12 gene. 2957 50