Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0700208 (scoliosis)
 8,574 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We describe three siblings from an Italian family affected by an autosomal recessive spinocerebellar degeneration. Gait ataxia, presenting between 38 and 45 years, was the first symptom in all three patients. Dysarthria, dysmetria, brisk tendon reflexes, extensor plantar response, and scoliosis were constant features. Disease progression was slow. Electrophysiologic studies demonstrated a slight reduction in sural nerve sensory action potential in only one patient. Analysis of GAA expansion within the X25 gene showed that patients were homozygous for the expansion, with the shorter expanded allele ranging from 120 to 156 triplets. The size of the GAA expansion may be smaller than we previously described. Such minimal expansions may result in atypical forms of Friedreich's ataxia.
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PMID:Broadened Friedreich's ataxia phenotype after gene cloning. Minimal GAA expansion causes late-onset spastic ataxia. 940 56

Friedreich ataxia is an autosomal recessive disorder caused by mutations in the FRDA gene that encodes a 210-amino acid protein called frataxin. An expansion of a GAA trinucleotide repeat in intron 1 of the gene is present in more than 95% of mutant alleles. Of the 83 people we studied who have mutations in FRDA, 78 are homozygous for an expanded GAA repeat; the other five patients have an expansion in one allele and a point mutation in the other. Here we present a detailed clinical and genetic study of a subset of 51 patients homozygous for an expansion of the GAA repeat. We found a correlation between the size of the smaller of the two expanded alleles and age at onset, age into wheelchair, scoliosis, impaired vibration sense, and the presence of foot deformity. There was no significant correlation between the size of the smaller allele and cardiomyopathy, diabetes mellitus, loss of proprioception, or bladder symptoms. The larger allele size correlated with bladder symptoms and the presence of foot deformity. The duration of disease is correlated with wheelchair use and the presence of diabetes, scoliosis, bladder symptoms and impaired proprioception, and vibration sense but no other complications studied.
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PMID:Clinical and genetic study of Friedreich ataxia in an Australian population. 1053 31

Friedreich's Ataxia (FA) is the commonest genetic cause of ataxia and is associated with the expansion of a GAA repeat in intron 1 of the frataxin gene. Iron accumulation in the mitochondria of patients with FA would result in hypersensitivity to oxidative stress. Mitochondrial DNA (mtDNA) could be considered a candidate modifier factor for FA disease, since mitochondrial oxidative stress is thought to be involved in the pathogenesis of this disease. We studied 25 Iranian patients (16 females and 9 males) from 12 unrelated families. DNA from each patient was extracted and frequency and length of (GAA)(n) repeat was analyzed using a long-range polymerase chain reaction (PCR) test. Also we investigated impact of GAA size on neurological findings, age of onset and disease development. In order to identify polymorphic sites and genetic background, the sequence of two hypervariable regions (HVR-I and HVR-II) of mtDNA was obtained from FA patients harbouring GAA trinucletide expansions. Alignment was made with the revised cambridge reference sequence (rCRS) and any differences recorded as single base substitution (SBS), insertions and deletions. Homozygous GAA expansion was found in 21 (84%) of all cases. In four cases (16%), no expansion was observed, ruling out the diagnosis of Friedreich's ataxia. In cases with GAA expansions, ataxia, scoliosis and pes cavus, cardiac abnormalities and some neurological findings occurred more frequently than in our patients without GAA expansion. Molecular analysis was imperative for diagnosis of Friedreich's ataxia, not only for typical cases, but also for atypical ones. Diagnosis bases only on clinical findings is limited, however, it aids in better screening for suspected cases that should be tested. Our results showed that the rate of D-loop variations was higher in FA patients than control (P<0.05). mtDNA deletions were present in 76% of our patients representing mtDNA damage, which may be due to iron accumulation in mitochondria.
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PMID:Identification and sizing of GAA trinucleotide repeat expansion, investigation for D-loop variations and mitochondrial deletions in Iranian patients with Friedreich's ataxia. 1658 13

This review concerns the development of small molecule therapeutics for the inherited neurodegenerative disease Friedreich ataxia (FRDA). FRDA is caused by transcriptional repression of the nuclear FXN gene, encoding the essential mitochondrial protein frataxin and accompanying loss of frataxin protein. Frataxin insufficiency leads to mitochrondrial dysfunction and progressive neurodegeneration, along with scoliosis, diabetes and cardiomyopathy. Individuals with FRDA generally die in early adulthood from the associated heart disease, the most common cause of death in FRDA. While antioxidants and iron chelators have shown promise in ameliorating the symptoms of the disease, there is no effective therapy for FRDA that addresses the cause of the disease, the loss of frataxin protein. Gene therapy and protein replacement strategies for FRDA are promising approaches; however, current technology is not sufficiently advanced to envisage treatments for FRDA coming from these approaches in the near future. Since the FXN mutation in FRDA, expanded GAA.TTC triplets in an intron, does not alter the amino acid sequence of frataxin protein, gene reactivation would be of therapeutic benefit. Thus, a number of laboratories have focused on small molecule activators of FXN gene expression as potential therapeutics, and this review summarizes the current status of these efforts, as well as the molecular basis for gene silencing in FRDA.
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PMID:Small molecules affecting transcription in Friedreich ataxia. 1782 40

Friedreich ataxia is an inherited, progressive, neurodegenerative disorder that is clinically heterogeneous. It is caused by a trinucleotide (GAA) repeat expansion resulting in frataxin loss and oxidative stress. We assessed clinical features including the development of cardiomyopathy and scoliosis and disease progression including loss of ambulation and interference with activities of daily living relative to the length of the GAA repeat, age of onset, and age of diagnosis in a retrospective cohort study of 61 genetically confirmed patients. The use of antioxidants such as vitamins, dietary supplements, and idebenone was also examined. Linear regression and Cox proportional hazard models assessed predictors to disease milestones. The shorter GAA allele accounted for part of the variability in the age of diagnosis (46%) and less in the age of onset (27%). Multivariate analysis demonstrated that age at diagnosis, which may incorporate other genetic and environmental factors, is more important than GAA length in predicting cardiomyopathy, scoliosis, and disease progression.
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PMID:Predictors of progression in patients with Friedreich ataxia. 1875 47

Friedreich ataxia (FRDA) is a rare autosomal recessive hereditary disorder that affects approximately 1 in 50,000 Caucasians. It is caused by hyperexpansion of GAA repeats in the first intron of the frataxin gene. Initial symptoms of FRDA usually appear around the beginning of the second decade of life. In addition to neuropathological disabilities such as ataxia, sensory loss, and muscle weakness, common signs are scoliosis, foot deformity, and hypertrophic cardiomyopathy. Approximately 10 % of patients with FRDA develop diabetes. The neuronopathy in the dorsal root ganglia, accompanied by the loss of peripheral sensory nerve fibres and the degeneration of posterior columns of the spinal cord, is a hallmark of the disease and is responsible for the typical combination of signs and symptoms specific to FRDA. Variation in neurophysiological abnormalities is correlated with the size of the GAA repeat expansion and likely accounts for individual variation in the progression of FRDA. Despite a range of disease severity, most patients will lose their ability to walk, stand, or sit without support within 10 to 15 years of disease onset. In addition to a review of the clinicopathological features of FRDA, a discussion of recent advances in our understanding of the underlying molecular mechanisms is provided.
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PMID:Friedreich ataxia: the clinical picture. 1928 44

Progressive signs of ataxia in a eight years old girl prompted neurological investigation. The girl had unstable gait with incoordination of limb movements, impairment of position and vibratory senses, dysarthria, pes cavus, positive Babinski sign and scoliosis. At the age of fourteen the girl was referred in a comatose condition, in a severe diabetic ketoacidosis. Ataxia and hypoactive knee and ankle jerks prompted the analysis of the frataxin gene (FXN; 606829). The most common molecular abnormality: GAA trinucleotide repeat expansion in intron 1 was found with + 300 GAA repeats (1490bp) (normal individuals have 5 to 30 GAA repeat expansions, whereas affected individuals have from 70 to more than 1,000 GAA triplets). Electrocardiogram showed diffuse T wave inversion with sinus bradycardia, while ultrasound revealed concentric, symmetric hypertrophy of left ventricle leading to the diagnosis of hyperthrophic cardiomyopathy. At the age of 14 years, the patient was bound to the wheel-chair, unable to walk. Her brother started to show ataxia at the age of 8 years, and subsequent analysis showed hyperthrophic cardiomyopathy, too. His mutational analysis revealed the same frataxin abnormality, with + 300 GAA repeats. So far, no signs of diabetes occurred. The parents are heterozygous with FXN of 9 -10 GAA (490 bp). Both children received a beta blocker, while the girl's diabetes mellitus was treated by insulin preparations. This is a report of two siblings with Fridreich ataxia and hyperthrophic cardiomyopathy. In addition, the girl developed type 1 diabetes mellitus.
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PMID:Friedreich ataxia (FA) associated with diabetes mellitus type 1 and hyperthrophic cardiomyopathy. 1948 41

Progressive signs of ataxia in a eight year old girl with hypo-active knee and ankle jerks, prompted the analysis of the frataxin gene (FXN; 606829). The most common molecular abnormality--GAA trinucleotide repeat expansion in intron 1--was found with +300 GAA repeats (1490 bp) (normal individuals have 5 to 30 GAA repeats expansions, whereas affected individuals have from 70 to more than 1000 GAA triplets). Additionally she had unstable gait with incoordination of limb movements, impairment of position and vibratory senses, dysarthria, pes cavus, positive Babinski sign and scoliosis. At the age of fourteen the girl was referred in a comatose condition, in severe diabetic ketoacidosis. Insulin dependent diabetes mellitus was since treated with insulin preparations. Electrocardiogram showed diffuse T wave inversion with sinus bradycardia, while ultrasound revealed concentric, symmetric hypertrophy of the left ventricle leading to the diagnosis of hypertrophic cardiomyopathy. At the age of 14, she is bound to the wheelchair, unable to walk. Her brother started to show ataxia at the age of 8 years and subsequent analysis also showed hypertrophic cardiomyopathy. His mutational analysis revealed the same frataxin abnormality with +300 GAA repeats. So far, no signs of diabetes occurred. The parental DNA was not available for analysis.
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PMID:Friedreich's ataxia (FA) associated with diabetes mellitus type 1 and hypertrophic cardiomyopathy: analysis of a FA family. 1953 71

This report describes two families who presented with autosomal recessive ataxia. By means of Polymerase Chain Reaction (PCR) molecular testing we identified expansions in the gene encoding Frataxin (FTX) that is diagnostic of Friedreich ataxia. A history of reproductive loss in the two families, prominent scoliosis deformity preceding the onset of ataxic gait, the presence of a sensitive axonal neuropathy, as well as the common origin of ancestors are unusual features of these families. These cases illustrate the importance of molecular diagnosis in patients with a recessive ataxia. The origin of the expanded gene and the GAA repeat size in the normal population are issues to be further investigated. The molecular diagnosis of Friedreich ataxia is now established in Cuba.
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PMID:Uncommon features in Cuban families affected with Friedreich ataxia. 2010 28

Friedreich ataxia (FRDA), the most common of the hereditary ataxias, is an autosomal recessive, multisystem disorder characterised by progressive ataxia, sensory symptoms, weakness, scoliosis and cardiomyopathy. FRDA is caused by a GAA expansion in intron one of the FXN gene, leading to reduced levels of the encoded protein frataxin, which is thought to regulate cellular iron homeostasis. The cerebellar and spinocerebellar dysfunction seen in FRDA has known effects on motor function; however until recently slowed information processing has been the main feature consistently reported by the limited studies addressing cognitive function in FRDA. This chapter will systematically review the current literature regarding the neuropathological and neurobehavioural phenotype associated with FRDA. It will evaluate more recent evidence adopting systematic experimental methodologies that postulate that the neurobehavioural phenotype associated with FRDA is likely to involve impairment in cerebello-cortico connectivity.
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PMID:Characterising the neuropathology and neurobehavioural phenotype in Friedreich ataxia: a systematic review. 2356 Mar 11


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