|
| ||
|
|
||
C282Y Mutation (c282y + mutation)
Selected AbstractsHemochromatosis genotypes and risk of 31 disease endpoints: Meta-analyses including 66,000 cases and 226,000 controls,HEPATOLOGY, Issue 4 2007Christina Ellervik Hemochromatosis genotypes have been associated with liver disease, diabetes mellitus, heart disease, arthritis, porphyria cutanea tarda, stroke, neurodegenerative disorders, cancer, and venous disease. We performed meta-analyses including 202 studies with 66,263 cases and 226,515 controls to examine associations between hemochromatosis genotypes C282Y/C282Y, C282Y/H63D, C282Y/wild type, H63D/H63D, and H63D/wild type versus wild type/wild type and 9 overall endpoints and 22 endpoint subgroups. We also explored potential sources of heterogeneity. For liver disease, the odds ratio for C282Y/C282Y versus wild type/wild type was 3.9 (99% confidence interval: 1.9,8.1) overall, 11 (3.7,34) for hepatocellular carcinoma, 4.1 (1.2,14) for hepatitis C, and 10 (2.1,53) for nonalcoholic steatohepatitis. For porphyria cutanea tarda, the odds ratios were 48 (24,95) for C282Y/C282Y, 8.1 (3.9,17) for C282Y/H63D, 3.6 (1.8,7.3) for C282Y/wild type, 3.0 (1.6,5.6) for H63D/H63D, and 1.7 (1.0,3.1) for H63D/wild type versus wild type/wild type. Finally, for amyotrophic lateral sclerosis, the odds ratio was 3.9 (1.2,13) for H63D/H63D versus wild type/wild type. These findings were consistent across individual studies. The hemochromatosis genotypes were not associated with risk for diabetes mellitus, heart disease, arthritis, stroke, cancer, or venous disease in the overall analyses; however, the odds ratio for C282Y/C282Y versus wild type/wild type was 3.4 (1.1,11) for diabetes mellitus among North Europeans. Conclusion: In aggregate, clinically ascertained cases who are homozygous for the C282Y mutation are associated with a 4,11,fold risk of liver disease, whereas all 5 hemochromatosis genotypes are associated with a 2,48,fold risk of porphyria cutanea tarda, and H63D/H63D is associated with a 4-fold risk of amyotrophic lateral sclerosis. These results, mainly from case-control studies, cannot necessarily be extrapolated to the general population. (HEPATOLOGY 2007.) [source] Effects of Alcohol Consumption on Iron Metabolism in Mice with Hemochromatosis MutationsALCOHOLISM, Issue 1 2007Jonathan M. Flanagan Background: Alcoholic liver disease is associated with increased hepatic iron accumulation. The liver-derived peptide hepcidin is the central regulator of iron homeostasis and recent animal studies have demonstrated that exposure to alcohol reduces hepcidin expression. This down-regulation of hepcidin in vivo implies that disturbed iron sensing may contribute to the hepatosiderosis seen in alcoholic liver disease. Alcohol intake is also a major factor in expression of the hemochromatosis phenotype in patients homozygous for the C282Y mutation of the HFE gene. Methods: To assess the effect of alcohol in mice with iron overload, alcohol was administered to mice with disrupted Hfe and IL-6 genes and Tfr2 mutant mice and their respective 129x1/SvJ, C57BL/6J, and AKR/J wild-type congenic strains. Iron absorption, serum iron levels, and hepcidin expression levels were then measured in these mice compared with water-treated control mice. Results: Alcohol was shown to have a strain-specific effect in 129x1/SvJ mice, with treated 129x1/SvJ mice showing a significant increase in iron absorption, serum iron levels, and a corresponding decrease in hepcidin expression. C57BL/6J and AKR/J strain mice showed no effect from alcohol treatment. 129x1/SvJ mice heterozygous or homozygous for the Hfe knockout had a diminished response to alcohol. All 3 strains were shown to have high blood alcohol levels. Conclusions: The effect of alcohol on iron homeostasis is dependent on the genetic background in mice. In an alcohol-susceptible strain, mutation of the Hfe gene diminished the response of the measured iron indices to alcohol treatment. This indicates that either maximal suppression of hepcidin levels had already occurred as a result of the Hfe mutation or that Hfe was a component of the pathway utilized by EtOH in suppressing hepcidin production and increasing iron absorption. [source] Asymptomatic individuals at genetic risk of haemochromatosis take appropriate steps to prevent disease related to iron overloadLIVER INTERNATIONAL, Issue 3 2008Katrina J. Allen Abstract Background/Aims: If community screening for hereditary haemochromatosis is to be considered, compliance with preventative measures and absence of significant psychological morbidity must be demonstrated. Methods: Workplace screening for the HFE C282Y mutation and then clinical care for C282Y homozygotes was instituted. Data were collected on understanding of test results, perceived health status and anxiety for C282Y homozygotes compared with controls. Uptake of clinical care, compliance and response to treatment and changes in diet were monitored for up to 4 years for C282Y homozygotes. Results: After 11 307 individuals were screened, 40/47 (85%) newly identified C282Y homozygotes completed questionnaires 12 months after diagnosis compared with 79/126 (63%) of controls. Significantly more C282Y homozygotes correctly remembered their test result compared with controls (95 vs 51%, P<0.0001). No significant difference in perceived health status was observed within or between the two groups at 12 months compared with baseline. Anxiety levels decreased significantly for C282Y homozygotes at 12 months compared with before testing (P<0.05). Forty-five of the 47 (95.8%) C282Y homozygotes accessed clinical care for at least 12 months. All 22 participants requiring therapeutic venesection complied with treatment for at least 12 months (range 12,47 months). Conclusion: Individuals at a high genetic risk of developing haemochromatosis use clinical services appropriately, maintain their health and are not ,worried well'. Population genetic screening for haemochromatosis can be conducted in the work place in a way that is acceptable and beneficial to participants. [source] Liver pathology in compound heterozygous patients for hemochromatosis mutationsLIVER INTERNATIONAL, Issue 4 2002Maximilian Schöniger-Hekele Abstract: Background: While hepatic pathology of homozygous carriers of the C282Y mutation of the HFE haemochromatosis gene is well defined, the impact of the C282Y/H63D compound heterozygous carrier state is unknown. Aims: To evaluate the range of hepatic pathology in C282Y/H63D compound heterozygous patients. Patients: 25 C282Y/H63D compound heterozygous patients with and without known underlying liver disease underwent liver biopsies for evaluation or abnormal liver tests. Eleven cadaveric liver donors with HFE wild type served as controls. Methods: Mutations in the HFE gene were detected by polyacrylamide gel electrophoresis (PAGE) separation of digested polymerase chain reaction (PCR)-amplificates. The extent of light microscopic changes of liver architecture were studied on haematoxylin, eosin (H. E.) stains. In addition, the extent and the distribution of iron deposition was graded on Prussian blue-stained sections and hepatic iron was quantified by atom absorption spectroscopy. Serum ferritin concentration and the transferrin saturation index were measured using routine laboratory methods. Results: Patients without underlying liver disease (n = 15): Hepatic inflammation was seen in only 8% but fibrosis was found in 36% of compound heterozygous patients. Eighty six percent of those patients had stainable iron predominantly found in Rappaport's zone 1 and 2, but all had a liver iron-index < 1.9. Transferrin saturation was found elevated in 36% of compound heterozygous patients. Patients with liver fibrosis showed significantly higher ferritin levels than patients without liver fibrosis (1110 ng/mL versus 307 ng/mL, p < 0.05). Patients with underlying disease (n = 10): In compound heterozygous patients, 77% had hepatic inflammation and 88% fibrosis. Stainable iron (44%) was less frequently found than in patients without underlying liver disease. Hepatic iron-index in patients with underlying liver disease was always below 1.17; transferrin saturation was elevated in only 22% of the compound heterozygous patients. Histologic hepatic iron-index was significantly lower in patients with underlying disease (median 0.047) as compared to patients without underlying liver disease (median 0.274, P < 0.05). Conclusions: The underlying liver disease determines the extent of hepatic pathology seen in livers of compound heterozygous patients. However, considerable histologic fibrosis can also be found in compound heterozygous patients without underlying liver disease. [source] Raised serum ferritin predicts non-response to interferon and ribavirin treatment in patients with chronic hepatitis C infectionLIVER INTERNATIONAL, Issue 3 2002S Distante Abstract: Background/Aim: Previous studies have indicated that response to interferon therapy is inversely proportional to the amount of body iron stores. We have studied the relationship between serum ferritin, transferrin saturation, liver iron, presence of HFE-C282Y gene mutation and response to treatment in patients with chronic hepatitis C infection. Methods: Two hundred and fifty-six naive, HCV-RNA positive patients (60% males, median age 38 years, range 21,70) were treated with interferon and ribavirin for 6 months. Iron indices and the presence of the C282Y mutation were measured. In 242 (94%) patients iron deposition were determined by Perls staining method. Patients with negative HCV-RNA at 6 months after the end of treatment were defined as sustained viral responders. Results: Non-responders (n = 127) had significantly higher median s-ferritin values compared with sustained viral responders (130 µg/L vs. 75 µg/L P < 0.001). There was no difference in transferrin saturation among the two response groups. Only 23% (4/7) of patients with Perls grade 1 in liver biopsies responded to treatment vs. 54% (122/225) patients without iron deposition (P = 0.02), however, 10/13-non-responders had HCV genotype one. Two patients (0.8%) were homozygous for the C282Y mutation, 36 patients were heterozygous (14%). Among mutation carriers 26/38 achieved sustained response compared with 102/216 non-carriers (68% vs. 48%, P = 0.02). In a multivariate analysis s-ferritin (P = 0.030) and C282Y carrier status (P = 0.012) remained independent predict of sustained response. Conclusions: Raised s-ferritin values predicate non-response to interferon-ribavirin therapy in hepatitis C patients. Response rate in C282Y mutation carriers seems greater than in non-carriers. [source] Analysis of haemochromatosis gene mutations in a population from the Mediterranean BasinLIVER INTERNATIONAL, Issue 4 2001Salvatore Campo Abstract:Background/Aims: The C282Y mutation in the haemochromatosis gene (HFE) located on chromosome 6 has been identified as the main genetic basis of hereditary haemochromatosis (HH). Two more mutations of that gene, H63D and S65C, appear to be associated with milder forms of HH. A high allele frequency for C282Y and H63D mutations was reported in populations from North Europe, while incomplete information is available for individuals from the Mediterranean Basin where C282Y homozygotes comprise a smaller percentage of HH cases. In this study we investigated the allele frequency of HFE mutations and the association between HFE mutations and cases of HH in a population from the South of Italy (Sicily and Calabria). In addition, we evaluated a possible association between HFE mutations and either chronic liver disease or type II diabetes. Patients and Methods: Three hundred and twenty-seven individuals (654 chromosomes) were tested for C282Y, H63D and S65C mutations of the HFE gene by restriction fragment length polymorphism. Four had HH, 23 had hepatocellular carcinoma, 100 had chronic liver disease, 100 had type II diabetes, and 100 were healthy controls. Results: Both C282Y and S65C mutations were each detected in one of the 654 chromosomes analysed (allele frequency=0.15%), while H63D change was found in 122 chromosomes (allele frequency=18.6%) and was equally distributed in all the categories examined. One healthy individual had compound heterozygosity for C282Y and H63D mutations. The frequency of C282Y in this Southern Italian sample was the lowest yet reported for a population of European origin. None of the four HH patients was either homozygous or heterozygous for C282Y. Conclusions: In Mediterranean populations from Southern Italy the C282Y mutation occurs sporadically and HFE polymorphisms seem to have little diagnostic relevance. [source] Liver transplantation for hereditary hemochromatosisLIVER TRANSPLANTATION, Issue 8 2001David J. Brandhagen MD Although hereditary hemochromatosis (HHC) is relatively common, it is an uncommon indication for orthotopic liver transplantation (OLT). The diagnosis of HHC in patients with end-stage liver disease is difficult because many of these patients have elevated serum and tissue iron levels. Of patients undergoing OLT with iron stores in the range typical for HHC, approximately 10% are homozygous for the C282Y mutation. Most studies published to date noted decreased survival in patients who underwent OLT for HHC compared with those who underwent OLT for other indications. Death in patients with HHC was caused by increased infectious and cardiac complications. Decreased post-OLT survival in patients with iron overload appears to be independent of HFE gene status. This suggests that regardless of the cause, iron overload may be detrimental in patients undergoing OLT. Follow-up of patients undergoing OLT for HHC and case reports of the inadvertent transplantation of a liver from a donor with HHC has furthered our understanding of the pathophysiological state of iron overload in HHC. [source] Hyperferritinemia and iron overload in type 1 Gaucher disease,AMERICAN JOURNAL OF HEMATOLOGY, Issue 7 2010Philip Stein Hyperferritinemia occurs in Gaucher disease but its clinical spectrum or its association with systemic iron overload and HFE mutations are not known. In 114 patients with Type 1 Gaucher disease, we determined serum ferritin, transferrin saturation and HFE genotype. The results were correlated with the extent of hepatosplenomegaly, overall Gaucher disease severity score index, and response to enzyme replacement therapy. In a subset of patients with radiological and/or laboratory evidence of systemic iron overload, liver biopsy was performed. There was a mean 3.7-fold elevation of serum ferritin over the upper limit of normal (ULN). Prior splenectomy was associated with most severe hyperferritinemia compared to patients with intact spleen (6.53 × ULN vs. 2.69 × ULN, P = 0.003). HFE genotyping revealed two patients homozygous for H63D mutation and 30% of patients heterozygote carriers of H63D mutation; no patients harbored C282Y mutation; there was no correlation of ferritin with HFE genotype. Ferritin level correlated with liver volume (Pearson correlation coefficient = 0.254, P = 0.035) and it was negatively correlated with hemoglobin (r = ,0.315, P = 0.004); there was no relationship with other indicators of Gaucher disease activity. Enzyme replacement therapy (ERT) resulted in amelioration of hyperferritinemia: 707 ± 898 ng/ml vs. 301 ± 310 ng/ml (P = 0.001), transferrin saturation remained normal. Three patients were suspected of clinical iron overload, confirmed on liver biopsy. Iron accumulation was variably noted in hepatocytes and Kupffer cells. There is a high prevalence of hyperferritinemia in Type 1 Gaucher disease that is associated with indicators of disease severity, reversed by ERT and is not related to HFE mutations. Am. J. Hematol. 2010. © 2010 Wiley-Liss, Inc. [source] Porphyria cutanea tarda in south-east New South WalesAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 4 2002Ian McCrossin SUMMARY Thirteen patients with porphyria cutanea tarda diagnosed between 1994 and 2000 were reviewed to evaluate the precipitating factors and associations of porphyria cutanea tarda in a regional area of coastal and rural NSW. The majority had more than one precipitating factor, with excess alcohol intake, mutations in the haemochromatosis gene, chronic hepatitis C infection and oestrogen therapy being the most common. Antibodies to the hepatitis C virus were detected in 25% and these patients presented at a younger age. Of the patients tested for the two known haemochromatosis gene mutations, six (46%) had at least one copy of the C282Y mutation. Two (15%) patients were homozygous for the C282Y mutation and two (15%) were compound heterozygous for the C282Y and H63D mutations. All patients responded to venesection, which is the treatment of choice for the majority of patients with porphyria cutanea tarda. [source] H63D homozygotes with hyperferritinaemia: is this genotype, the primary cause of iron overload?EUROPEAN JOURNAL OF HAEMATOLOGY, Issue 1 2007Carles De Diego Abstract Objectives:,Hereditary haemochromatosis is a disease that affects iron metabolism and leads to iron overload. Homozygosity for the H63D mutation is associated with increased transferrin saturation (TS) and ferritin levels. Our objective was to find out if the homozygosity of H63D mutation was the primary cause of iron overload. Patients and methods:,We studied 45 H63D homozygotes (31 males and 14 females) with biochemical iron overload and/or clinical features of haemochromatosis. The simultaneous detection of 18 known HFE, TFR2 and FPN1 mutations and sequencing of the HAMP gene were performed to rule out the possible existence of genetic modifier factors related with iron overload. Results:,Values of biochemical iron overload, measured as percentage TS and serum ferritin concentration (SF), in our H63D homozygotes were significantly higher in patients than in controls: TS 55 ± 15% vs. 35 ± 15% and SF 764 (645,883) ,g/L vs. 115 (108,123) ,g/L for patients and controls, respectively. These H63D homozygotes presented extreme hyperferritinaemia and no additional mutations in HFE, TFR2, FPN1 and HAMP genes were detected. Conclusions:,The lack of additional mutations in our H63D homozygotes suggests that this genotype could be the primary cause of iron overload in these patients. Despite our results, we cannot entirely discount the possibility that one or more genetic modifier factor exists, simply because we were unable to find it, although there was a precedent in the HFE gene. Genetic modifier factors have been described for C282Y mutations in the HFE gene, but at the present time they have never been reported in H63D homozygotes. [source] | ||||||||||||||||||||||