Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.5.7.1 (methylenetetrahydrofolate reductase)
 2,116 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Homocysteine levels and the frequency of heterozygous methylenetetrahydrofolate reductase (MTHFR) C677T mutation are increased in open-angle glaucoma. Since homocysteine can induce vascular injury, alterations in extracellular matrix remodelling, and neuronal cell death, these findings may have important implications for understanding glaucomatous optic neuropathy.
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PMID:Homocysteine and risk of open-angle glaucoma. 1248 90

A 39-year-old man was admitted with a sudden visual loss in the left eye. Visual acuities were 10/10 on the right and 1/10 on the left. Fundus examination did not show any abnormalities. Visual acuity improved to 10/10 and visual field defect regressed in the following 2 weeks. Three years later, the patient returned with acute visual loss in the right eye. Visual acuities were 2/10 on the right and 10/10 on the left. Right optic disc had blurred margins with mild oedema. The tests revealed methylenetetrahydrofolate reductase A1298C mutation with positive lupus anticoagulant and hyperhomocysteinaemia. Enoxaparin was initialised with vitamin B12 supplementation. Complete visual recovery occurred in the following 3 weeks in both eyes. Thrombophilic screening seems to be important in the treatment and prevention of an attack in the second eye of patients with non-arteritic anterior ischaemic optic neuropathy.
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PMID:Bilateral consecutive optic neuropathy in a patient with thrombophilia. 2377 68

Malabsorptive bariatric surgery is rapidly becoming a major cause of copper deficiency given the increasing prevalence of these procedures for morbid obesity. Acquired copper deficiency can present with clinically significant hematologic and neurological manifestations. Although hematologic manifestations of copper deficiency are rapidly reversible, significant neurological improvement after copper supplementation therapy is unusual and many patients remain debilitated and may only experience, at best, stabilization of the neurological manifestations. Here we present a case of an undiagnosed copper deficiency several years after bariatric gastric bypass surgery, in a patient who concomitantly used zinc-containing denture cream for several years, associated with anemia, neutropenia, myelopathy, respiratory failure, and bilateral optic neuropathy, which caused major vision loss. This patient was also a heterozygote carrier of the 5,10-methylenetetrahydrofolate reductase A1298C gene polymorphism, which may affect copper metabolism. Intravenous copper repletion resulted in rapid correction of hematologic indices. However, neurological manifestations, including vision loss responded only modestly to copper supplementation, despite achieving normal blood copper concentrations. Clinicians should consider copper deficiency in patients at risk, as in this case, as a delayed diagnosis can lead to irreversible disability due to neurological manifestations.
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PMID:Optic neuropathy, myelopathy, anemia, and neutropenia caused by acquired copper deficiency after gastric bypass surgery. 2458 48

The present study enrolled 251 diabetic patients, including 101 with neuropathy and 150 without neuropathy. Of the 150 patients, 100 had no complications, such as retinopathy, nephropathy, or neuropathy. Polymerase chain reaction-restriction fragment length polymorphism analysis was used to identify methylenetetrahydrofolate reductase gene variants. Plasma homocysteine levels were also measured. Homocysteine levels and the frequency of hyperhomocysteinemia were significantly higher in patients with diabetic peripheral neuropathy compared with diabetic patients without neuropathy (P < 0.05). In logistic regression analysis with neuropathy as the dependent variable, the frequency of C677T in methylenetetrahydrofolate reductase was significantly higher in patients with diabetic peripheral neuropathy compared with patients without diabetic complications. Homocysteine levels were significantly higher in patients with diabetic peripheral neuropathy carrying the 677T allele and low folic acid levels. In conclusion, hyperhomocysteinemia is an independent risk factor for diabetic neuropathy in Chinese patients with diabetes. The C677T polymorphism in methylenetetrahydrofolate reductase and low folic acid levels may be risk factors for diabetic peripheral neuropathy in Chinese patients with diabetes.
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PMID:Is the C677T polymorphism in methylenetetrahydrofolate reductase gene or plasma homocysteine a risk factor for diabetic peripheral neuropathy in Chinese individuals? 2553 64

Homocysteine remethylation disorders are rare inherited disorders caused by a deficient activity of the enzymes involved in the remethylation of homocysteine to methionine. The adolescent/adult-onset remethylation disorders are rarely reported. We analyzed the clinical and genetic characteristics of seven cases with adolescent/adult remethylation disorders, including 5 cases of the cobalamin C disease (cblC) and 2 cases of the methylenetetrahydrofolate reductase deficiency. The average onset age was 21.1 (range 14 to 40) years. All patients complained of gait disturbances. Other common symptoms included psychiatric symptoms (5/7) and cognitive decline (4/7). Acute encephalopathy, dysarthria, anorexia, vomiting, ketoacidosis, anemia, cataract, and hand tremor were also observed. The mean total homocysteine in serum when the patients were diagnosed was 94.6 (range 53.1-154.5) mol/L. Electrophysiological studies revealed neuropathy in the lower limbs (6/7). The brain MRI showed reversible altered signal from the dorsal portions of the cerebellar hemispheres (1/7), periventricular hyperintensity (2/7), and delayed/impaired myelination (2/7). The sural nerve biopsy performed in one case showed a modest loss of myelinated fibers. Five patients showed heterozygous mutations of the MMACHC gene, including c.482G>A (5/5), c.609G>A (2/5), and c.658-660delAAG (3/5). Two patients showed heterozygous mutations of the MTHFR gene, including c.698C>A (2/2), c.698C>G (1/2), and c.236+1G>A (1/2). The patients responded well to the treatments with significant improvements. Adolescent/adult-onset remethylation disorders are easily misdiagnosed. We recommend testing the serum homocysteine concentrations in young/adult patients with unexplained neuro-psychotic symptoms. Furthermore, individuals with significantly elevated serum homocysteine concentrations should be further tested by organic acid screening and genetic analysis.
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PMID:Adolescent/adult-onset homocysteine remethylation disorders characterized by gait disturbance with/without psychiatric symptoms and cognitive decline: a series of seven cases. 3300 Mar 30