Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019158 (hepatitis)
 30,205 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

This paper reports clinical and metabolic studies of two Italian siblings with a novel form of persistent isolated hypermethioninaemia, i.e. abnormally elevated plasma methionine that lasted beyond the first months of life and is not due to cystathionine beta-synthase deficiency, tyrosinaemia I or liver disease. Abnormal elevations of their plasma S-adenosylmethionine (AdoMet) concentrations proved they do not have deficient activity of methionine adenosyltransferase I/III. A variety of studies provided evidence that the elevations of methionine and AdoMet are not caused by defects in the methionine transamination pathway, deficient activity of methionine adenosyltransferase II, a mutation in methylenetetrahydrofolate reductase rendering this activity resistant to inhibition by AdoMet, or deficient activity of guanidinoacetate methyltransferase. Plasma sarcosine (N-methylglycine) is elevated, together with elevated plasma AdoMet in normal subjects following oral methionine loads and in association with increased plasma levels of both methionine and AdoMet in cystathionine beta-synthase-deficient individuals. However, plasma sarcosine is not elevated in these siblings. The latter result provides evidence they are deficient in activity of glycine N-methyltransferase (GNMT). The only clinical abnormalities in these siblings are mild hepatomegaly and chronic elevation of serum transaminases not attributable to conventional causes of liver disease. A possible causative connection between GNMT deficiency and these hepatitis-like manifestations is discussed. Further studies are required to evaluate whether dietary methionine restriction will be useful in this situation.
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PMID:Glycine N-methyltransferase deficiency: a novel inborn error causing persistent isolated hypermethioninaemia. 1159 49

Chronic infection of viral hepatitis is the main cause of liver cancer. There were many studies assessing the associations of methylenetetrahydrofolate reductase (MTHFR) Ala222Val polymorphism with risks of hepatitis and hepatitis-related liver cancer, but no consistent results were reported. To investigate the associations of MTHFR Ala222Val polymorphism with risks of hepatitis and hepatitis-related liver cancer, we performed a meta-analysis of published case-control studies. Eligible studies were searched from PubMed and Chinese National Knowledge Infrastructure (CNKI) databases. The odds ratio (OR) and corresponding 95 % confidence interval (95 %CI) were used to assess the associations. Twenty-one individual studies with a total of 8,187 subjects were included. Overall, MTHFR Ala222Val polymorphism was not significantly associated with risks of liver cancer, hepatitis-related liver cancer, and non-hepatitis-related liver cancer. However, MTHFR Ala222Val polymorphism was significantly associated with risk of hepatitis infection (Val vs. Ala: OR = 1.15, 95 %CI 1.01-1.32, P = 0.03; ValVal/AlaVal vs. AlaAla: OR = 1.37, 95 %CI 1.11-1.68, P = 0.003). Therefore, MTHFR Ala222Val polymorphism is significantly associated with risk of hepatitis infection but not liver cancer. More studies are needed to further assess the association between MTHFR Ala222Val polymorphism and hepatitis-related liver cancer.
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PMID:Associations between MTHFR Ala222Val polymorphism and risks of hepatitis and hepatitis-related liver cancer: a meta-analysis. 2415 11

C677T (Ala>Val, rs1801133 C>T), a non-synonymous variant of methylenetetrahydrofolate reductase (MTHFR) gene, has been found to be associated with an impair enzyme activity of MTHFR. The relationship of MTHFR rs1801133 with hepatocellular carcinoma (HCC) has been extensively investigated. However, the findings were conflicting. Recently, more investigations have been conducted on the relationship of MTHFR rs1801133 with HCC. To obtain a more precise assessment on the effect of this non-synonymous variant to the development of HCC, a pooled-analysis was performed. This meta-analysis consisted of 19 independent case-control studies. By using the odds ratio (OR) combined with 95% confidence interval (CI), the relationship of MTHFR rs1801133 with HCC risk was determined. A total of 19 independent case-control studies were included. Finally, 6,102 HCC cases and 6,526 controls were recruited to examine the relationship of MTHFR rs1801133 with HCC risk. In recessive model (TT vs. CC/CT), the findings reached statistical significance (OR, 0.90; 95%CI, 0.82-0.98; P = 0.016). Subgroup analysis also found an association between MTHFR rs1801133 polymorphism and the decreased risk of HCC in hepatitis/virus related patients (recessive model: OR, 0.85; 95%CI, 0.72-0.99; P = 0.035, and allele model: OR, 0.90; 95%CI, 0.81-0.99; P = 0.028). Subgroup analyses indicated that extreme heterogeneity existed in Asian population, larger sample size investigation, hospital-based study and normal/healthy control subgroups. The shape of Begger's seemed symmetrical. Egger's linear regression test also confirmed these evaluations. Sensitivity analyses suggested that our findings were stable. In summary, our results highlight that MTHFR rs1801133 polymorphism decreases HCC susceptibility. The relationship warrants a further assessment.
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PMID:Methylenetetrahydrofolate reductase C677T (Ala>Val, rs1801133 C>T) polymorphism decreases the susceptibility of hepatocellular carcinoma: a meta-analysis involving 12,628 subjects. 3201 Sep 31