Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A 35 year-old male was admitted to our hospital because of convulsive seizures. His parents are first cousins. No other members of his family have similar symptoms. He showed mental retardation since childhood. At age 14, he had generalized convulsive seizures that were intractable. Bilateral cataracts were found and extracted at age 18. He noticed bilateral swellings at Achilles tendons at around 25 years of age. Physical examination revealed bilateral swellings of Achilles tendons. Neurologically, he showed poor intellectual ability, hyperreflexia with positive Babinski's sign and cerebellar ataxia. Marked elevations of cholestanol level (53.84 micrograms/ml; normal: 2.71 +/- 0.81, n = 17) and cholestanol/cholesterol ratio (2.20%; normal: 0.16 +/- 0.05, n = 17) were detected in serum. EEG showed abnormal background activities with bursts of high voltage slow theta activities. MRI study showed high intensity lesions in globus pallidus and multiple lesions in white matter with long spin echo sequence. Oral administration of chenodeoxycholic acid improved EEG findings, serum cholestanol level and convulsive seizures. However, the MRI abnormalities remained unchanged, which suggested irreversible brain damage. We reviewed the previous reports of 144 cases of CTX. Fourteen cases had convulsive seizures. We stress that CTX is one the causes of symptomatic epilepsy.
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PMID:[A case of cerebrotendinous xanthomatosis with convulsive seizures]. 219 Jul 43

Cerebrotendinous xanthomatosis (CTX) is a hereditary disorder, which is inherited as an autosomally recessive disease, causing production of cholesterol and cholestanol xanthomas and mental retardation. The disease is caused by mutations in the gene for sterol 27-hydroxylase (CYP27A1). The only CTX patients diagnosed in Scandinavia are two Norwegian sisters from a consanguineous marriage. Here we have characterized the mutation and its functional consequences for the enzyme. Analysis of genomic DNA from cultured fibroblasts identified a base exchange C > T in position 1441, causing arginine at amino acid position 441 to be replaced by tryptophan. The same mutation was introduced by mutagenesis in the complimentary DNA (cDNA) for CYP27, ligated into the expression vector pcDNA4/HisMax and transfected into HEK293 cells. The mutated enzyme had less than 5% of the enzyme activity compared with the native enzyme. No abnormal catalytic products could be identified in the cell culture medium. Probably the mutation affects the haem binding within the holoenzyme. The mutation has also previously been reported in a Japanese family. This is the second example of a CTX-causing mutation that has been recognized in more than one population.
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PMID:Cerebrotendinous xanthomatosis: molecular characterization of two Scandinavian sisters. 1227 7

Cerebrotendinous xanthomatosis (CTX) is an autosomal recessive lipid storage disease caused by a deficiency of the mitochondrial enzyme 27-sterol hydroxylase (CYP27). We report a 53-year-old man, with an unusual phenotype of CTX. He had xanthomas since adolescence. He had no mental retardation and developed at 44 years a progressive neuropsychiatric phenotype, suggestive of fronto-temporal dementia according to clinical Neary criteria. Cataract and ataxia were absent. Cerebral MRI revealed diffuse hyperintense T2 abnormalities in the supratentorial white matter without cerebellar atrophy or lesions, while Technetium-99m-ECD brain SPECT revealed a severe cerebellar hypoperfusion. Serum cholestanol level was elevated with excessive urinary bile alcohols excretion. Mutation analysis revealed that he was compound heterozygous for two mutations in the CYP27A1 gene: 1016 C > T (exon 5) on one allele and a novel mutation, 1435C > G (exon 8) on the other allele. A follow-up study was conducted to evaluate the effects of chenodeoxycholic acid (CDCA) and simvastatin treatment during 3 years. In spite of this treatment, cognitive functions declined but no other signs of neurological deterioration appeared.
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PMID:Unusual cerebrotendinous xanthomatosis with fronto-temporal dementia phenotype. 1627 84

Cerebrotendinous Xanthomatosis (CTX) is a rare autosomal recessive lipid storage disease caused by sterol 27-hydroxylase (CYP27) deficiency. We report three CTX siblings that shared a novel mutation of the CYP27A1 gene. These siblings presented with elevated cholestanol levels and typical manifestations such as tendon xanthomas, cataracts, osteopenia, mental retardation, cerebellar ataxia and peripheral neuropathy. All shared the same genetic mutation, c.1146_1151delins and c.1214G>A of CYP27A1. All were treated with 750 mg/day chenodeoxycholic acid (CDCA). In conclusion, one should consider the possibility of CTX in any individual with normocholesterolemic xanthomatosis, early-onset cataracts, mental retardation, cerebellar ataxia and peripheral neuropathy.
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PMID:Three siblings with Cerebrotendinous Xanthomatosis: a novel mutation in the CYP27A1 gene. 2195 93

Cerebrotendinous xanthomatosis (CTX) is a rare and treatable autosomal recessive disease. The diagnosis should be suspected in the presence of a suggestive clinical triad characterized by early-onset cataract, tendinous xanthomata and neurological symptoms and signs, notably cerebellar ataxia, mental retardation and pyramidal syndrome.The diagnosis is confirmed by demonstrating an increased blood level of cholestanol, or/and by molecular genetic analysis.In typical cases, brain MRI shows bilateral hyperintensity of the cerebellar nucleus dentatus together with cerebral atrophy and leukoencephalopathy. The treatment is based on the administration of chenodeoxycholic acid. The aim is to restore the negative feedback on the enzymatic cascade altered by mutation in the gene CYP27 which induces a 27-hydroxylase deficiency
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PMID:[Cerebrotendinous xanthomatosis, a rare, severe, but treatable metabolic disorder]. 2375 6

Alkaline phosphatase (ALP) in humans comprises a family of four cell-surface phosphomonoester phosphohydrolase isozymes. Three genes separately encode the "tissue-specific" ALPs whereas the fourth gene encodes ubiquitous homodimeric "tissue-nonspecific" ALP (TNSALP) richly expressed in bone, liver, kidney, and developing teeth. TNSALP monomers have five putative N-linked glycosylation sites where different post-translational modifications account for this isozyme's distinctive physicochemical properties in different organs. Three bone-derived TNSALP (BALP) isoforms (B/I, B1, and B2) are present in healthy serum, whereas a fourth BALP isoform (B1x) can circulate in chronic kidney disease. Herein, we report a healthy boy with persistent hyperphosphatasemia due to BALP levels two- to threefold higher than age-appropriate reference values. High-performance liquid chromatography, electrophoresis, heat inactivation, catalysis inhibition, and polyethylene glycol precipitation revealed increased serum B/I, B1, and B2 differing from patterns found in skeletal diseases. B/I was ~23-fold elevated. Absence of mental retardation and physical stigmata excluded Mabry syndrome, the ALP-anchoring disorder causing hyperphosphatasemia. Routine biochemical studies indicated intact mineral homeostasis. Serum N-terminal propeptide of type I procollagen (P1NP) level was normal, but C-terminal cross-linking telopeptide of type I collagen (CTX) level was elevated. However, radiological studies showed no evidence for a generalized skeletal disturbance. Circulating pyridoxal 5'-phosphate, a TNSALP natural substrate, was not low despite the laboratory hyperphosphatasemia, thereby suggesting BALP phosphohydrolase activity was not elevated endogenously. Mutation analysis of the ALPL gene encoding TNSALP revealed no defect. His non-consanguineous healthy parents had serum total ALP activity and BALP protein levels that were normal. Our patient's sporadic idiopathic hyperphosphatasemia could reflect altered post-translational modification together with increased expression and/or impaired degradation of BALP.
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PMID:Persistent idiopathic hyperphosphatasemia from bone alkaline phosphatase in a healthy boy. 3247 45