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HFE Mutations (hfe + mutation)
Selected AbstractsGenetic testing for HFE hemochromatosis in Australia: The value of testing relatives of simple heterozygotesJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7 2002JULEEN A CAVANAUGH AbstractBackground : It is unclear whether screening of relatives of C282Y and H63D heterozygotes (other than compound heterozygotes) for hemochromatosis will detect sufficient numbers of cases to justify introduction of this screening strategy. Methods : Conditional probabilities were determined using published Australian allele frequencies and penetrance data to determine the detection rate of hemochromatosis by testing the siblings and offspring of heterozygotes (subjects with only one HFE mutation). Results : The number of individuals who are at risk of developing increased body iron stores because of HFE mutations is substantially higher (1 in 80) than previously estimated. In addition, 33% of the Australian population are heterozygous for either C282Y or H63D. Based on population estimates, the relative risk to the offspring of C282Y and H63D heterozygotes of developing increased iron stores is 4.1 and 1.5, respectively, while the relative risk to each sibling is 2.3 and 1, respectively. The risk of developing clinical features of hemochromatosis or hepatic fibrosis is likely to be substantially lower. Conclusions : Although the detection rate from testing the families of unaffected heterozygotes is low, this can be justified as a clinically useful screening strategy. At the present time this strategy should be restricted to first-degree relatives of heterozygotes. Further studies are recommended to determine if cascade genetic screening is a cost-effective alternative to general population screening. © 2002 Blackwell Publishing Asia Pty Ltd [source] Does chloroquine therapy of porphyria cutanea tarda influence liver pathology?INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 11 2009U Wollina MD Background, Porphyria cutanea tarda (PCT) is regularly associated with changes in liver tissue. On the other hand, systematic investigations are lacking on whether there is a correlation between the severity of liver damage and chloroquine treatment. Patients and methods, During a 20-year period, liver biopsies were obtained in 89 patients with PCT confirmed by biochemical analysis of urine and feces and low-dose chloroquine therapy. Seventeen patients with alcohol-induced liver disease were excluded. In 8 of 63 patients, only a single biopsy was available. Classification of liver damage was performed according to the Riedel score. Electron microscopy was available from 24 patients. In a second group of patients, the HFE status was investigated and Berlin blue stains of liver biopsies were performed. Results, There was no correlation between the duration of cutaneous symptoms and liver pathology. After 12 months chloroquine treatment, 45 patients (81%) disclosed an improvement of liver pathology, nine (16%) had no change, and a worsening was observed in one patient (3%). All patients achieved a complete clinical and biochemical remission. In 13 of 16 patients with a relapse, there was again a deterioration of liver damage. Patients with HFE mutations had a significant higher risk (P < 0.05) for hepatic siderosis. Conclusions, The severity of liver damage was not correlated with the disease duration. Chloroquine treatment resulted in PCT remission (clinical and biochemical) and in 81% to an improvement of liver morphology. [source] Population-based study of the relationship between mutations in the hemochromatosis (HFE) gene and arthritisJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 3 2006Colin A Sherrington Abstract Background and Aim:, Mutations in the hemochromatosis (HFE) gene are carried by one in three individuals of British Isles descent and may result in increased iron stores. These increased iron stores could potentially induce or exacerbate diseases, such as arthritis, in which iron has a role in pathogenesis. Although arthritis is a well-known association of clinically overt hereditary hemochromatosis, controversy surrounds the role of mutations in the HFE gene as risk factors for arthritis. The aim of the present study was to determine whether mutations in the HFE gene are associated with an increased prevalence of arthritis. Methods:, A population-based study was conducted in Busselton, Western Australia, of the prevalence of arthritis in 1372 individuals of British Isles descent. Participants completed a questionnaire and general physical examination. Analysis for C282Y and H63D HFE mutations was undertaken. Unadjusted and adjusted odds ratios (OR) were calculated for the relationship between HFE mutations and the prevalence of self-reported, doctor-diagnosed arthritis. Results:, There was no association between the presence of HFE mutations and the prevalence of self-reported, doctor-diagnosed arthritis (C282Y/wild type (WT) adjusted OR = 1.041 (95% confidence interval (CI) 0.68,1.61), H63D/WT OR = 0.76 (95% CI 0.53,1.08), C282Y/C282Y OR = 0.39 (95% CI 0.04,3.63), C282Y/H 63D OR = 0.808 (95% CI 0.27,2.42), H63D/H63D OR = 0.419 (95% CI 0.13,1.36)). Overall adjusted OR for arthritis in participants with one or more HFE mutations was 0.81 (95% CI 0.61,1.09). Conclusions:, Mutations of the HFE gene are not risk factors for arthritis in populations of British Isles descent. [source] Genetic testing for HFE hemochromatosis in Australia: The value of testing relatives of simple heterozygotesJOURNAL OF GASTROENTEROLOGY AND HEPATOLOGY, Issue 7 2002JULEEN A CAVANAUGH AbstractBackground : It is unclear whether screening of relatives of C282Y and H63D heterozygotes (other than compound heterozygotes) for hemochromatosis will detect sufficient numbers of cases to justify introduction of this screening strategy. Methods : Conditional probabilities were determined using published Australian allele frequencies and penetrance data to determine the detection rate of hemochromatosis by testing the siblings and offspring of heterozygotes (subjects with only one HFE mutation). Results : The number of individuals who are at risk of developing increased body iron stores because of HFE mutations is substantially higher (1 in 80) than previously estimated. In addition, 33% of the Australian population are heterozygous for either C282Y or H63D. Based on population estimates, the relative risk to the offspring of C282Y and H63D heterozygotes of developing increased iron stores is 4.1 and 1.5, respectively, while the relative risk to each sibling is 2.3 and 1, respectively. The risk of developing clinical features of hemochromatosis or hepatic fibrosis is likely to be substantially lower. Conclusions : Although the detection rate from testing the families of unaffected heterozygotes is low, this can be justified as a clinically useful screening strategy. At the present time this strategy should be restricted to first-degree relatives of heterozygotes. Further studies are recommended to determine if cascade genetic screening is a cost-effective alternative to general population screening. © 2002 Blackwell Publishing Asia Pty Ltd [source] Enrichment of HFE mutations in Swedish patients with familial and sporadic form of porphyria cutanea tardaJOURNAL OF INTERNAL MEDICINE, Issue 6 2004P. Harper First page of article [source] Influence of HFE gene polymorphism on the progression and treatment of chronic hepatitis CJOURNAL OF VIRAL HEPATITIS, Issue 2 2004P. Lebray Summary., We analysed liver histology findings in a large cohort of patients with chronic hepatitis C and in roughly half of them their response to interferon- , -based on iron parameters and HFE status. Histological activity and virological response to antiviral therapy (n = 146) were analysed in 273 immunocompetent and nonalcoholic patients with chronic hepatitis C, in terms of serum iron load, intrahepatic iron load (n = 110) and HFE mutations. Patients who were heterozygous for the C282Y and H63D mutations exhibited higher iron serum parameters than subjects without these mutations. The intrahepatic iron load was higher in H63D patients only. No association was observed between HFE mutations and histological activity. Increased iron parameters were associated with liver disease severity by univariate analysis only. Genotype 1 and ferritinaemia were associated with a poor response to antiviral therapy, whereas the H63D mutation emerged as a positive predictive factor for end of treatment and sustained antiviral response. Therefore, in chronic hepatitis C patients serum and intrahepatic iron levels were weakly correlated with histological activity, while HFE mutations were not. As for the response to interferon- ,, elevated ferritinaemia constituted a negative predictive factor whereas the H63D mutation was a positive one. The H63D mutation might form part of an immunogenetic profile influencing the response to interferon therapy. [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] Current Directions in Hemochromatosis Research: Towards an Understanding of the Role of Iron Overload and the HFE Gene Mutations in the Development of Clinical DiseaseNUTRITION REVIEWS, Issue 1 2003Article first published online: 16 SEP 200 Since the discovery of a candidate gene (HFE) thought to be involved in the development of hereditary hemochromatosis, there has been much interest in the potential use of genetic testing as a screening tool for the disease in the general population. However, a recent study suggests that less than 1% of subjects who are homozygous for the gene mutations will go on to develop the full-blown disease of hereditary hemochromatosis, historically termed "bronzed diabetes." The study also suggests that homozygotes have no higher risk of mortality or of any clinically significant morbidity than normal control subjects. This conclusion contradicts earlier findings that linked iron overload and HFE mutations to a number of devastating diseases, including cardiovascular disease, diabetes, and cancer. [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] 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] | ||||||||||