Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004134 (ataxia)
 15,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Abetalipoproteinaemia (Bassen-Kornzweig syndrome), an autosomal recessive inherited disease, up to now has been described in 53 instances in the world literature. Neurological symptoms were reported in 34 of them. Ataxia, loss of proprioceptive sensation, and areflexia characterize this disorder, resembling Friedreich's ataxia. Other signs, which may be inconstantly found, are weakness, diminution of cutaneous sensation, and in the later course an atypical retinitis pigmentosa. Laboratory examinations show acanthocytosis, lowered concentrations of serum cholesterol, triglycerides and phospholipids and as the pathognomonic feature of this disease absence of beta-lipoproteins. Reduced serum concentrations of fat soluble vitamin are secondary effects of this metabolic disorder. In a few cases there are connections to familial hypobeta-lipoproteinaemia, which is autosomal dominantly inherited. Therapeutic trials with a controlled dietary intake of fat may cause an improvement of clinical symptoms, additional doses of fat-soluble vitamin, if given during the early stages of the disease are said to prevent from retinopathy but do not seem to influence the development and course of neuropathy.
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PMID:[Neurological symptoms in a-beta-lipoproteinemia (author's transl)]. 25 73

A family of 6 siblings, 4 of which have Hallgren's syndrome, i.e., retinitis pigmentosa, congenital deafness and ataxia is described. Hallgren's series in Sweden is referred to. This affection was ascribed by Hallgren to a single gene with almost complete penetrance. However, 3 brothers of the present series show neurological anomalies not present in the Swedish cases.
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PMID:[Hallgren's syndrome in one family: retinitis pigmentosa, congenital deafness and ataxia]. 58 86

A 7-year-old boy presented with bilateral ptosis and atypical retinitis pigmentosa. Before age two, he had had an Fe-refractory anemia, with neutropenia and thrombopenia. Just prior to the ophthalmic examination, the patient developed lactate acidosis, muscular hypotonia, ataxia and increased protein in the spinal fluid. Pancytopenia, pancreas dysfunction and growth retardation are the main features of Pearson's syndrome, most children not surviving beyond age three. The cause of Pearson's syndrome in our patient turned out to be a 5 kb deletion in the mitochondrial DNA. Similar deletions have been described in the Kearns-Sayre syndrome. It seems that children who survive the initial phase of Pearson's syndrome, may develop Kearns-Sayre syndrome.
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PMID:Kearns-Sayre's syndrome developing in a boy who survived pearson's syndrome caused by mitochondrial DNA deletion. 130 30

In the past few years several syndromes have been associated with lesions of the human mitochondrial DNA. MtDNA is a small, circular extra-nuclear chromosome encoding essential components of the respiratory chain. MtDNA-related syndromes can be divided into two groups: mitochondrial encephalomyopathies, characterized by the presence of ragged-red fibres (RRF) as the morphological hallmark, or "pure" encephalopathies with no gross morphological abnormalities in muscle. The first group includes myoclonic epilepsy with ragged-red fibres (MERRF), mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS), Kearns-Sayre syndrome (KSS), chronic progressive external ophthalmoplegia (CPEO) and a new entity, maternally inherited myopathy and cardiomyopathy. The second group includes Leber's Hereditary Optic Neuroretinopathy (LHON) and the newly described ataxia-retinitis pigmentosa-dementia complex. Three kinds of molecular lesions have been identified: point mutations of protein encoding mtDNA-genes (similar to yeast mit- mutations); point mutations of mtDNA-tRNA genes (similar to yeast syn- mutations); and large-scale rearrangements of mtDNA (similar to yeast rho- mutations). In general, "mit-" mutations are responsible for non-RRF encephalopathies, while "syn-" and "rho-" mutations are associated with mitochondrial encephalomyopathies with RRF. Furthermore, point mutations (mit- and syn-) are usually maternally- inherited, while large-scale mtDNA rearrangements are either sporadic or inherited as mendelian traits. In most cases, the molecular detection of the known defects of mtDNA can be carried out by non-invasive techniques, thus making it an easy and relatively inexpensive procedure in the differential diagnosis of the mitochondrial disorders, a rapidly expanding area of clinical neurology.
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PMID:Defects of mitochondrial DNA. 134 53

One case of ataxic, pyramidal and demential syndrome associated with retinitis pigmentosa occurred in a family with Huntington's disease (36 patients among 7 generations). The disease started at 15 years of age. Ataxia was transiently attenuated by isoniazid. The patient died of the disease at 26 years of age.
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PMID:[A progressive case of ataxia in a family of Huntington's chorea]. 144 54

We have previously described a family with a neurological syndrome comprising neurogenic muscle weakness, ataxia, retinitis pigmentosa, and variable sensory neuropathy, seizures, and mental retardation or dementia. This is associated with a heteroplasmic point mutation of mtDNA at bp 8993. The mother of a severely affected child underwent prenatal diagnosis in two further pregnancies. Analysis of chorionic villus samples showed a higher proportion of mutant mtDNA on both occasions, and this was reflected in the majority of fetal tissues, including brain and muscle. Prenatal diagnosis is a rational approach to the prevention of severe diseases caused by point mutations of mtDNA but is currently hampered by incomplete knowledge concerning the proportion of mutant mtDNA: its relationship to disease severity, how it may change during fetal and postnatal development, and its tissue distribution.
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PMID:Prenatal diagnosis of mitochondrial DNA8993 T----G disease. 153 98

A female infant showing lacticacidemia, hypotonia, and neurodegenerative disease died at 7 mo of age. Autopsy revealed lesions typical of Leigh disease, both in the basal ganglia and in the brain stem. A maternal aunt and uncle died 1 year and 5 mo, respectively, after following a similar clinical course, while another uncle, presently 33 years of age, has retinitis pigmentosa and ataxia and is mentally retarded. PCR restriction-digest analysis of mtDNA isolated from the proband revealed a T-to-G change at position 8993, creating a new AvaI restriction site. The mutation present in the ATP 6 gene results in the substitution of an arginine residue for a leucine. The indexed patient had greater than 95% abnormal mtDNA in her skin fibroblasts, brain, kidney, and liver tissues, as measured by laser densitometry. The maternal aunt who died at age 1 year had greater than 95% abnormal mtDNA in her lymphoblasts. The uncle with retinitis pigmentosa had 78% and 79% abnormal mtDNA in his skin fibroblasts and lymphoblasts, respectively, while an asymptomatic maternal aunt and her son had no trace of this mutation. The mother of the index case had 71% and 39% abnormal mtDNA in her skin fibroblasts and lymphoblasts, respectively, showing that the heteroplasmy can be variable, on a tissue-specific basis, within one individual. This shows that mtDNA mutations at 8993 can produce the clinical phenotype of Leigh disease in addition to the phenotype of ataxia and retinitis pigmentosa described by Holt et al.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Heteroplasmic mtDNA mutation (T----G) at 8993 can cause Leigh disease when the percentage of abnormal mtDNA is high. 830 53

A clinical, genetic and epidemiological study of hereditary ataxias and paraplegias was conducted within a defined area (Cantabria) in Northern Spain from 1974 to 1986. The series comprised 48 index cases and 65 affected relatives. On prevalence day, 103 patients were alive, giving a prevalence of 20.2 cases per 100,000. There were 24 patients (18 families) with Friedreich's ataxia (FA), 12 (6 families) with early onset cerebellar ataxia (EOCA) differing from FA, 6 (3 families) with dominantly transmitted late onset cerebellar ataxia (LOCA), 11 with 'idiopathic' LOCA, 49 (9 families) with 'pure' hereditary spastic paraplegia (HSP), and 1 patient with congenital cerebellar ataxia. The prevalence found here is comparable with the highest figures described in previous surveys. This may in part be due to the great number of secondary cases in our series. A high frequency of parental consanguinity occurred in FA patients, 'pseudodominant' inheritance being observed in 1 family. The clinical features were those of classical FA except for later onset and slower course in 1 family, and retained tendon reflexes in the lower limbs in 2 cases. Such data indicate the need for modification of the essential criteria for the disease. EOCA included 4 patients with normoreflexic ataxia and 1 patient with ataxia and luteinizing hormone-releasing hormone deficiency. In addition, there were 7 patients from 2 unrelated families with a homogeneous syndrome characterized by autosomal recessive inheritance, cerebellar ataxia, retinitis pigmentosa and sensory neuropathy. This syndrome is therefore a well defined nosological entity to be added to the list of autosomal recessive mendelian phenotypes. The clinical picture of patients with LOCA was either a 'pure' cerebellar or a 'cerebellar-plus' syndrome. Genetic subgroups of 'pure' HSP were autosomal dominant type I in 5 families and type II in 2, and autosomal recessive in 2 families.
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PMID:Hereditary ataxias and paraplegias in Cantabria, Spain. An epidemiological and clinical study. 204 54

A variable combination of developmental delay, retinitis pigmentosa, dementia, seizures, ataxia, proximal neurogenic muscle weakness, and sensory neuropathy occurred in four members of a family and was maternally transmitted. There was no histochemical evidence of mitochondrial myopathy. Blood and muscle from the patients contained two populations of mitochondrial DNA, one of which had a previously unreported restriction site for AvaI. Sequence analysis showed that this was due to a point mutation at nucleotide 8993, resulting in an amino acid change from a highly conserved leucine to arginine in subunit 6 of mitochondrial H(+)-ATPase. There was some correlation between clinical severity and the amount of mutant mitochondrial DNA in the patients; this was present in only small quantities in the blood of healthy elderly relatives in the same maternal line.
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PMID:A new mitochondrial disease associated with mitochondrial DNA heteroplasmy. 213 62

An 18-month-old infant presented with a history of arrest of neurological development from the age of eight months, with progressive ataxia, deafness, retinitis pigmentosa and hepatomegaly. Biochemical investigations revealed an elevated plasma phytanic acid level and deficiency of phytanic acid oxidase in skin fibroblasts. Histopathological findings in a liver biopsy were similar to those reported in infantile phytanic acid storage disease. Unexpected findings were the presence of elevated levels of plasma pipecolic acid, and elevated plasma long-chain fatty acid ratios, biochemical findings previously considered to be diagnostic of Zellweger's hepato-cerebro-renal syndrome, and of adrenoleucodystrophy, respectively. Recent biochemical evidence suggests that this patient, and other similar cases that have recently come to our attention, may have a fundamental defect in the peroxisomal enzyme system.
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PMID:Infantile Refsum's disease: a peroxisomal storage disorder? 243 38


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