Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Folic acid supplementation may help prevent the following three common and important disorders: neural tube defect pregnancies, ischemic heart disease and strokes, and possibly colon cancer. Several studies have irrefutably established that folic acid supplementation in proper doses reduces neural tube defect pregnancies. Fortified food would be the most reliable way to address this health issue. Several epidemiologic reports have established a close link between hyperhomocysteinemia and ischemic heart disease. This is supported by evidence obtained from genetic defects leading to elevated plasma levels of homocysteine. There is reasonable evidence to conclude that hyperhomocysteinemia is the actual cause of excessive cardiac diseases. Again, folic acid supplementation in proper doses could potentially reduce ischemic heart disease by 40% There is also some evidence to suggest that folic acid treatment reduces the incidence of colon cancer. The reduction in all three health problems is dependent upon the dose of folic acid administered. The levels needed are rarely supplied by the daily food intake, even under ideal conditions, although breakfast cereals address this problem at least in part. It is proposed that flour be fortified because it is a food product heavily used by most people, and that governmental agencies should oversee such programs because they are responsible for setting public health policies.
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PMID:Fortifying food with folic acid. 1101 53

Hyperhomocysteinemia, a risk factor for cardiovascular disease, is caused by nutritional and/or genetic disruptions in homocysteine metabolism. The most common genetic cause of hyperhomocysteinemia is the 677C-->T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene. This variant, with mild enzymatic deficiency, is associated with an increased risk for neural tube defects and pregnancy complications and with a decreased risk for colon cancer and leukemia. Although many studies have reported that this variant is also a risk factor for vascular disease, this area of investigation is still controversial. Severe MTHFR deficiency results in homocystinuria, an inborn error of metabolism with neurological and vascular complications. To investigate the in vivo pathogenetic mechanisms of MTHFR deficiency, we generated mice with a knockout of MTHFR: Plasma total homocysteine levels in heterozygous and homozygous knockout mice are 1.6- and 10-fold higher than those in wild-type littermates, respectively. Both heterozygous and homozygous knockouts have either significantly decreased S-adenosylmethionine levels or significantly increased S-adenosylhomocysteine levels, or both, with global DNA hypomethylation. The heterozygous knockout mice appear normal, whereas the homozygotes are smaller and show developmental retardation with cerebellar pathology. Abnormal lipid deposition in the proximal portion of the aorta was observed in older heterozygotes and homozygotes, alluding to an atherogenic effect of hyperhomocysteinemia in these mice.
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PMID:Mice deficient in methylenetetrahydrofolate reductase exhibit hyperhomocysteinemia and decreased methylation capacity, with neuropathology and aortic lipid deposition. 1118 67

The common 5,10-methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism causes decreased activity of this enzyme and can be associated with mild-to-moderate hyperhomocysteinemia in homozygotes, particularly when there is folic acid deficiency, as well as with vascular dementia, arterial thrombosis, venous thrombosis, neural-tube defects, and fetal loss. When folic acid intake is sufficient, homozygotes for MTHFR 677T appear to be protected against colon cancer and acute lymphatic leukemia, and fetuses bearing this genotype have an augmented survival. The distribution of MTHFR 677T is worldwide, but its frequency in different populations varies extensively. In the present study, we addressed the question of whether the MTHFR 677T alteration has an ancestral origin or has occurred repeatedly. We analyzed the frequency distribution of the previously described polymorphism A1298C in exon 7 and of three intronic dimorphisms, in white Israelis (Jews and Arabs), Japanese, and Ghanaian Africans. The 677T allele was, remarkably, associated with one haplotype, G-T-A-C, in white and Japanese homozygotes. Among the Africans, analysis of maximum likelihood also disclosed an association with the G-T-A-C haplotype, although none of the 174 subjects examined was homozygous for MTHFR 677T. These results suggest that the MTHFR 677T alteration occurred on a founder haplotype that may have had a selective advantage.
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PMID:The frequent 5,10-methylenetetrahydrofolate reductase C677T polymorphism is associated with a common haplotype in whites, Japanese, and Africans. 1178 70

Autosomal-dominant polycystic kidney disease (ADPKD) is a systemic disease with multiple extrarenal manifestations. It accounts for 7% to 11% of patients receiving dialysis or renal transplantation (RT) for end-stage renal disease (ESRD) in Europe. We analyzed retrospectively the causes of death, the prevalence of cardiovascular risk factors (CVRF) and the patient and graft survivals in 62 consecutive ADPKD patients who received 63 cadaveric grafts (29 men and 34 women), of the 600 RTs performed between 1980-2001. The diagnosis of ADPKD was established by family history and ultrasound techniques. At present, 50 patients (79.4%) have functioning grafts, with a mean follow-up of 84.7 months (range, 12-255), and 13 patients have lost their grafts. The main cause of failure was patient death with a functioning graft (9 cases). Malignancies occurred in 5 patients, including 2 lymphomas, 1 renal carcinoma, 1 pancreas sarcoma, and 1 lung cancer associated with infection. Three patients died of cardiocerebrovascular events, and 1 patient of pneumonia. One patient lost the graft after decreasing the immunosuppression for an obstructing colon cancer. Three additional patients now on dialysis lost their grafts due to chronic rejection in 2 cases and primary nonfunction in 1 case. The prevalence of cardiovascular risk factors among the 50 patients with functional grafts were: hypertension, 70%; hypercholesterolemia, 62%; hyperhomocysteinemia, 30%; hyperfibrinogenemia, 68%; increased lipoprotein (a), 18%; microalbuminuria, 22%; hyperuricemia, 48%; hyperparathyroidism, 24%; overweight status, 24%; and nonlethal myocardial infarction, 10%. We conclude that ADPKD patients have good graft and patient survivals, and that the presence of malignancy is the main cause of death and graft failure at our center.
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PMID:Autosomal-dominant polycystic kidney disease: high prevalence of graft loss for death-related malignancies and cardiovascular risk factors. 1296 69