Common Mutation in the HFE Gene Modifies Recovery After Intracerebral Hemorrhage.

BACKGROUND: Intracerebral hemorrhage (ICH) is characterized by bleeding into the brain parenchyma. During an ICH, iron released from the breakdown of hemoglobin creates a cytotoxic environment in the brain through increased oxidative stress. Interestingly, the loss of iron homeostasis is associated with the pathological process of other neurological diseases. However, we have previously shown that the H63D mutation in the homeostatic iron regulatory (HFE) gene, prevalent in 28% of the White population in the United States, acts as a disease modifier by limiting oxidative stress. The following study aims to examine the effects of the murine homolog, H67D HFE, on ICH. METHODS: An autologous blood infusion model was utilized to create an ICH in the right striatum of H67D and wild-type mice. The motor recovery of each animal was assessed by rotarod. Neurodegeneration was measured using fluorojade-B and mitochondrial damage was assessed by immunofluorescent numbers of CytC+ (cytochrome C) neurons and CytC+ astrocytes. Finally, the molecular antioxidant response to ICH was quantified by measuring Nrf2 (nuclear factor-erythroid 2 related factor), GPX4 (glutathione peroxidase 4), and FTH1 (H-ferritin) levels in the ICH-affected and nonaffected hemispheres via immunoblotting. RESULTS: At 3 days post-ICH, H67D mice demonstrated enhanced performance on rotarod compared with wild-type animals despite no differences in lesion size. Additionally, H67D mice displayed higher levels of Nrf2, GPX4, and FTH1 in the ICH-affected hemisphere; however, these levels were not different in the contralateral, non-ICH-affected hemisphere. Furthermore, H67D mice showed decreased degenerated neurons, CytC+ Neurons, and CytC+ astrocytes in the perihematomal area. CONCLUSIONS: Our data suggest that the H67D mutation induces a robust antioxidant response 3 days following ICH through Nrf2, GPX4, and FTH1 activation. This activation could explain the decrease in degenerated neurons, CytC+ neurons, and CytC+ astrocytes in the perihematomal region, leading to the improved motor recovery. Based on this study, further investigation into the mechanisms of this neuroprotective response and the effects of the H63D HFE mutation in a population of patients with ICH is warranted.

Association between Polymorphisms of Hemochromatosis (HFE), Blood Lead (Pb) Levels, and DNA Oxidative Damage in Battery Workers.

Occupational exposure to lead (Pb) continues to be a serious public health concern and may pose an elevated risk of genetic oxidative damage. In Brazil, car battery manufacturing and recycling factories represent a great source of Pb contamination, and there are no guidelines on how to properly protect workers from exposure or to dispose the process wastes. Previous studies have shown that Pb body burden is associated with genetic polymorphisms, which consequently may influence the toxicity of the metal. The aim of this study was to assess the impact of Pb exposure on DNA oxidative damage, as well as the modulation of hemochromatosis (HFE) polymorphisms on Pb body burden, and the toxicity of Pb, through the analysis of 8-hydroxy-2'-deoxyguanosine (8-OHdG), in subjects occupationally exposed to the metal. Male Pb-exposed workers (n = 236) from car battery manufacturing and recycling factories in Brazil participated in the study. Blood and plasma lead levels (BLL and PLL, respectively) were determined by ICP-MS and urinary 8-OHdG levels were measured by LC-MS/MS, and genotyping of HFE SNPs (rs1799945, C → G; and 1800562, G → A) was performed by TaqMan assays. Our data showed that carriers of at least one variant allele for HFE rs1799945 (CG + GG) tended to have higher PLL than those with the non-variant genotype (ß = 0.34; p = 0.043); further, PLL was significantly correlated with the levels of urinary 8-OHdG (ß = 0.19; p = 0.0060), while workers that carry the variant genotype for HFE rs1800562 (A-allele) showed a prominent increase in 8-OHdG, as a function of PLL (ß = 0.78; p = 0.046). Taken together, our data suggest that HFE polymorphisms may modulate the Pb body burden and, consequently, the oxidative DNA damage induced by the metal.

Hemocromatosis: actualización clínica y diagnóstica / Hemochromatosis: clinical and diagnostic update

La hemocromatosis es un desorden en el cual la sobrecarga progresiva de hierro puede llevar a complicaciones sistémicas con gran morbimortalidad. Es una entidad clinicopatológica, con múltiples genes comprometidos y una fisiopatología común, con una expresión clínica y fenotípica variable, que depende de múltiples factores, tanto individuales como ambientales. Para su diagnóstico y seguimiento adecuado es necesario tener en cuenta elementos clínicos, bioquímicos y moleculares. En esta revisión, se presentan las generalidades de la hemocromatosis, además de sus mecanismos fisiopatológicos y moleculares, teniendo en cuenta su valor para el diagnóstico de la enfermedad. Adicionalmente, se describe la clasificación y un algoritmo diagnóstico propuestos recientemente por grupos de trabajo de expertos, así como las opciones de manejo y seguimiento de los pacientes con hemocromatosis

Hemochromatosis is a disorder in which progressive iron overload may lead to systemic complications with potential morbidity and mortality. It is a clinicopathologic entity that involves multiple genes and common pathophysiology, and has a variable clinical and phenotypic expression that depends on several individual and environmental factors. To make the diagnosis and perform a proper follow-up, clinical, biochemical, and molecular elements must be considered. This review aims to present the general characteristics of hemochromatosis, its molecular and pathophysiologic mechanisms, and their significance in the diagnosis of this disorder. In addition, a new classification and a proposed diagnostic algorithm by an expert working group are described, as well as management and follow-up options for patients with hemochromatosis

Quality of Life Scores Remained Different among the Genotypic Groups of Patients with Suspected Hemochromatosis, Even after Treatment Period.

BACKGROUND: Hemochromatosis is a genetic condition of iron overload caused by deficiency of hepcidin. In a previous stage of this study, patients with suspected hemochromatosis had their quality of life (QL) measured. We observed that QL scores differed among genotypic groups of patients. In this reported final phase of the study, the aims were to compare QL scores after a treatment period of approximately 3 years and to analyze a possible association of the serum ferritin values with QL scores. METHODS: Sixty-five patients were enrolled in this final phase and divided into group 1 (patients that showed primary iron overload and homozygous genotype for the HFE p.Cys282Tyr mutation) and group 2 (other kinds of genotypes). Short Form 36 (SF-36) was performed and consisted of eight domains with a physical and also a mental component. RESULTS: Both groups had a significant decrease in serum ferritin concentrations: group 1 had a variation from 1844 ± 1313 ng/mL to 281 ± 294 ng/mL, and group 2 had a variation from 1216 ± 631 ng/mL to 236 ± 174 ng/mL. Group 1 had a smaller mean value for these six SF-36 domains compared with group 2, indicating a worse QL. CONCLUSIONS: In this final stage, six domains demonstrated a difference among genotypic groups (role emotional and mental health, adding to the four of the initial phase), reassuring the impact of the identified genotype on the QL of hemochromatosis patients. Furthermore, despite that both patient groups demonstrated similar and significant decreases in serum ferritin values, no association was found between the decrease in this biological parameter and the SF-36 domains.

HFE hemochromatosis: an overview about therapeutic recommendations

Abstract Hemochromatosis is currently characterized by the iron overload caused by hepcidin deficiency. Large advances in the knowledge on the hemochromatosis pathophysiology have occurred due to a better understanding of the protein of the iron metabolism, the genetic basis of hemochromatosis and of other iron overload diseases or conditions which can lead to this phenotype. In the present review, the main aims are to show updates on hemochromatosis and to report a practical set of therapeutic recommendations for the human factors engineering protein (HFE) hemochromatosis for the p.Cys282Tyr (C282Y/C282Y) homozygous genotype, elaborated by the Haemochromatosis International Taskforce.

Lesões hepáticas associadas à hemocromatose hereditária / Liver lesions associated with hereditary hemochromatosis

RESUMO A hemocromatose hereditária (HH) é uma doença genética autossômica recessiva, a mais comum encontrada em caucasianos, causada pelo acúmulo de ferro em diferentes órgãos, predominantemente no fígado, causando sua disfunção. As mutações hereditárias relacionadas ao gene HFE representam quase 90% dos casos de hemocromatose entre as populações de descendência europeia. A absorção excessiva do ferro ocasiona acúmulo em órgãos como coração, pâncreas e fígado ocasionando diversas manifestações clínicas. Além dos sintomas gerais, a progressiva sobrecarga de ferro causa uma das principais complicações, a cirrose hepática. A regressão da fibrose pode ser alcançada após o tratamento, promovendo a remoção do estímulo e restaurando a função do fígado. Caso a HH não seja tratada ou o tratamento não tenha sido efetivo, o paciente pode evoluir para um estado fibrótico de cirrose irreversível, que pode culminar com o carcinoma hepatocelular (CHC), complicação responsável por 45% das mortes em pacientes com HH. Nesse sentido, nota-se a importância de compreender os métodos diagnósticos, rastreamento e tratamento, de maneira a possibilitar manejos precoces e evitar complicações potencialmente fatais. Além disso, o fato da população dos estados do sul do Brasil ser composta em sua maioria por descendentes norte-europeus - os mais acometidos pela HH - justifica a importância de literaturas e estudos clínicos mais recentes e realizados nessa região com o objetivo de compreender a evolução clínica da doença e estabelecer medidas preventivas para a manifestação de lesões hepáticas. PALAVRAS-CHAVE: Hemocromatose, HFE, diagnóstico, cirrose hepática, carcinoma hepatocelular

ABSTRACT Hereditary hemochromatosis (HH) is an autosomal recessive genetic disease, the most common found in Caucasians, caused by the accumulation of iron in different organs, predominantly in the liver, causing its dysfunction. Inherited mutations related to the HFE gene represent almost 90% of cases of hemochromatosis among populations of European descent. Excessive iron absorption causes accumulation in organs such as the heart, pancreas and liver, causing several clinical manifestations. In addition to the general symptoms, progressive iron overload causes one of the main complications, liver cirrhosis. Regression of fibrosis can be achieved after treatment, promoting stimulus removal and restoring liver function. If HH is not treated or the treatment has not been effective, the patient may progress to a fibrotic state of irreversible cirrhosis, which can culminate in hepatocellular carcinoma (HCC), a complication responsible for 45% of deaths in patients with HH. In this sense, the importance of understanding diagnostic methods, screening and treatment is noted, in order to enable early management and avoid potentially fatal complications. In addition, the fact that the population of the southern states of Brazil is composed mostly of North European descendants ­ the most affected by HH ­ justifies the importance of more recent literature and clinical studies carried out in this region in order to understand the clinical course of the disease and establish preventive measures for the manifestation of liver damage. KEYWORDS: Hemochromatosis, HFE, diagnosis, liver cirrhosis, hepatocellular carcinoma

[Non-HFE hemochromatosis: a case report]. / Hemocromatosis no ligada al gen HFE: a propósito de un caso.

Hereditary hemochromatosis (HH) consists of a progressive iron overload that leads to an abnormal accumulation of iron in different target organs; and, if not treated in time, can cause multi-organ dysfunction. Various genetic mutations associated with HH have been described, the most frequent is associated with the HFE-gene, which is found in 90% of cases. At present, therapeutic phlebotomy continues to be the treatment of choice for the management of this pathology. We report the case of a patient under follow-up for severe liver fibrosis, with persistence of a high ferrokinetic profile, who five years later was diagnosed with HH not associated to a mutation in the HFE-gene; He was managed with periodic phlebotomies, rapidly presenting a significant clinical improvement and decrease of ferritin levels.

Aspectos relevantes en hemocromatosis hereditaria / Relevant features in hereditary hemochromatosis

La hemocromatosis hereditaria es una enfermedad que se caracteriza por la sobrecarga sistémica de hierro y se asocia a múltiples mutaciones genéticas que conducen a una producción inadecuadamente baja de la hormona hepcidina o a una alteración en la unión de la hepcidina a la ferroportina. Esto tiene como resultado un aumento de la absorción intestinal y el depósito de cantidades excesivas de hierro en las células, lo cual, a su vez, si no se corrige, genera daño tisular. La expresión clínica puede variar desde individuos completamente asintomáticos, hasta pacientes con cirrosis hepática a temprana edad, y eventualmente carcinoma hepatocelular. Habitualmente, el diagnóstico no es invasivo e incluye el examen clínico, la evaluación de los parámetros de hierro plasmático, imágenes y pruebas genéticas. El principal tratamiento es la flebotomía, pero terapias alternativas como la suplementación con hepcidina son un tema de investigación actual.

Hereditary hemochromatosis is a disease characterized by systemic iron overload of genetic origin, that leads to an inadequately low production of the hormone hepcidin or a reduction in hepcidinferroportin binding. This results in an increased intestinal absorption and the deposit of excessive amounts of iron in cells, which in turn results in tissue damage if not treated. The clinical expression can vary from completely asymptomatic individuals, to patients with liver cirrhosis at an early age, and eventually hepatocellular carcinoma. Diagnosis is usually noninvasive and includes clinical examination, assessment of plasma iron levels, imaging studies, and genetic testing. The main medical treatment is phlebotomy, but alternative therapies such as hepcidin supplementation are the subject of current research.

Leukocyte telomere length is associated with iron overload in male adults with hereditary hemochromatosis.

BACKGROUND: Hereditary hemochromatosis (HH) is a primary iron overload (IO) condition. Absolute telomere length (ATL) is a marker of cellular aging and DNA damage associated with chronic diseases and mortality. AIM: To evaluate the relationship between ATL and IO in patients with HH. METHODS: Cross-sectional study including 25 patients with HH: 8 with IO and 17 without IO (ferritin < 300 ng/ml) and 25 healthy controls. Inclusion criteria were: age > 18 years, male sex and HH diagnosis. Patients with diabetes or other endocrine and autoimmune diseases were excluded. ATL was measured by real-time PCR. RESULTS: HH patients with IO were older (P<0.001) and showed higher ferritin concentration (P<0.001). Patients with HH, disregarding the iron status, showed higher glucose and body mass index (BMI) than controls (both P<0.01). ATL was shorter in patients with IO than controls [with IO: 8 (6-14), without IO: 13 (9-20), and controls: 19 (15-25) kilobase pairs, P<0.01]; with a linear trend within groups (P for trend <0.01). Differences in ATL remained statistically significant after adjusting by age, BMI and glucose (P<0.05). DISCUSSION: Patients with IO featured shorter ATL while patients without IO showed only mild alterations vs. controls. Screening for IO is encouraged to prevent iron-associated cellular damage and early telomere attrition.

Association of the polymorphisms of the genes APOC3 (rs2854116), ESR2 (rs3020450), HFE (rs1799945), MMP1 (rs1799750) and PPARG (rs1801282) with lipodystrophy in people living with HIV on antiretroviral therapy: a systematic review.

The aim of this study was to perform a systematic review to identify data reported in the literature concerning the association of APOC3 (rs2854116), ESR2 (rs3020450), HFE (rs1799945), MMP1 (rs1799750) and PPARG (rs1801282) polymorphisms with lipodystrophy in people living with HIV (PLWHIV) on antirretroviral therapy. The research was conducted in six databases and the studies were selected in two steps. First, a search was undertaken in the following electronic databases: PubMed, Science Direct, Medline, World Wide Science, Directory of Open Access Journals, Scielo, Lilacs and Medcarib. The titles and abstracts of 24,859 articles were read to select those that match the elegibilty criteria. Five papers that addressed the association of HAART, lipodystrophy and polymorphisms were selected for the review. There was no association between the polymorphisms of the genes APOC3 and PPARG and lipodystrophy. Another study described an association between the variant allele (G) of HFE and protection concerning the development of lipoatrophy (0.02) when compared with the reference allele (C). On the other hand, the variant allele (T) of the ESR2 gene was associated with the development of lipoatrophy (p = 0.007) when compared with the reference allele (C). In addition, the genotype and the variant allele of the gene MMP1 (2G) were associated with lipodystrophy in PLWHIV on HAART (p = 0.0002 and p = 0.0008, respectively). Therefore, further studies with other populations, involving PLWHIV on HAART are necessary to better understand the role of genetic markers, which may be involved in a predisposition to lipodystrophy.

Novel Mutation in the Hemojuvelin Gene (HJV) in a Patient with Juvenile Hemochromatosis Presenting with Insulin-dependent Diabetes Mellitus, Secondary Hypothyroidism and Hypogonadism.

BACKGROUND Juvenile hemochromatosis is a rare genetic disease that leads to intense iron accumulation. The disease onset usually occurs before the third decade of life and causes severe dysfunction in various organs. The most classical clinical findings are hypogonadotropic hypogonadism, cardiomyopathy, liver fibrosis, glycemic changes, arthropathy and skin pigmentation. However, secondary hypothyroidism is not reported in these patients. Juvenile hemochromatosis has an autosomal recessive inheritance and might be type 2A or type 2B, due to mutation in either the hemojuvelin gene (HJV) or hepcidin antimicrobial peptide (HAMP) gene. CASE REPORT A 26-year-old female patient was admitted with a recent history of diabetic ketoacidosis. Three months after that admission, she presented with arthralgia, diffuse abdominal pain, adynamia, hair loss, darkening of the skin and amenorrhea. Severe iron overload was found and findings in the hepatic biopsy were compatible with hemochromatosis. An upper abdominal magnetic resonance imaging (MRI) showed iron deposition in the liver and pancreas and pituitary MRI exhibited accumulation on the anterior pituitary. After 16 months the patient presented with dyspnea and lower limb edema, and cardiac MRI indicated iron deposition in the myocardium. The patient was diagnosed with juvenile hemochromatosis presenting with hypogonadotropic hypogonadism, cardiomyopathy, insulin-dependent diabetes mellitus, and secondary hypothyroidism. A novel homozygous mutation, c.697delC, in the HJV gene was detected. CONCLUSIONS We describe for the first time a severe and atypical case of juvenile hemochromatosis type 2A presenting classical clinical features, as well as secondary hypothyroidism resulting from a novel mutation in the HJV gene.

Prevalence and characteristics of anti-HCV positivity and chronic hepatitis C virus infection in HFE p.C282Y homozygotes.

INTRODUCTION AND AIM: Observations of hepatitis C virus (HCV) infection in adults with hemochromatosis are limited. MATERIALS AND METHODS: We determined associations of serum ferritin (SF) with anti-HCV in non-Hispanic white North American adults in a post-screening examination. Cases included p.C282Y homozygotes (regardless of screening transferrin saturation (TS) and SF) and participants (regardless of HFE genotype) with high screening TS/SF. Controls included participants without p.C282Y or p.H63D who had normal screening TS/SF. Participants with elevated alanine aminotransferase underwent anti-HCV testing. We determined prevalence of chronic HCV infection in consecutive Alabama and Ontario referred adults with HFE p.C282Y homozygosity. RESULTS: In post-screening participants, anti-HCV prevalence was 0.3% [95% CI: 0.02, 2.2] in 294 p.C282Y homozygotes, 9.5% [7.2, 12.3] in 560 Cases without p.C282Y homozygosity, and 0.7% [0.2, 2.3] in 403 Controls. Anti-HCV was detected in 7.2% of 745 participants with and 0.8% of 512 participants without elevated SF (odds ratio 9.9 [3.6, 27.6]; p<0.0001). Chronic HCV infection prevalence in 961 referred patients was 1.0% (10/961) [95% confidence interval (CI): 0.5, 2.0]. Ten patients with chronic HCV infection had median age 45y (range 29-67) and median SF 1163µg/L (range 303-2001). Five of eight (62.5%) patients had biopsy-proven cirrhosis. CONCLUSIONS: Odds ratio of anti-HCV was increased in post-screening participants with elevated SF. Prevalence of anti-HCV in post-screening participants with HFE p.C282Y homozygosity and chronic HCV infection in referred adults with HFE p.C282Y homozygosity in North America is similar to that of Control participants with HFE wt/wt and normal screening TS/SF.

Juvenile hemochromatosis with multi-organ involvement diagnosed at autopsy.

Hereditary hemochromatosis (HH) includes various disorders in iron metabolism producing iron deposits in several organs. HH is classified according to the HFE gene mutation. HH type I is characterized by HFE gene mutation, while types II, III and IV are due to other conditions. Juvenile hemochromatosis (JH) is related to hemojuvelin mutation, which is a regulatory peptide of the hepcidin protein, which regulates iron absorption. We report a case of JH and offer a concise review of the literature. A 14-year-old girl, with no secondary sexual characteristics, presented with abdominal pain, cough and dyspnoea. Clinical examination revealed right lower lobe consolidation, pleural effusion, cardiomegaly and an ejection fraction of 20%, with no response to treatment. On autopsy she was seen to have pleural and pericardial effusion, dilated cardiomyopathy, liver cirrhosis and pancreatic fibrosis. Prussian blue stain showed iron overload in these organs. JH with hypogonadism, cardiomyopathy and cirrhosis was diagnosed.

Cirrhosis in Hemochromatosis: Independent Risk Factors in 368 HFE p.C282Y Homozygotes.

INTRODUCTION AND AIM: We sought to identify independent risk factors for cirrhosis in HFE p.C282Y homozygotes in a cross-sectional study. MATERIAL AND METHODS: We evaluated 368 p.C282Y homozygotes who underwent liver biopsy and compared characteristics of those with and without cirrhosis. We performed multivariable logistic regression on cirrhosis with: age; sex; race/ethnicity; diabetes; blood pints/units donated voluntarily; erythrocyte pints/units received; iron supplement use; alcohol intake, g/d; body mass index, kg/m2; swollen/tender 2nd/3rd metacarpophalangeal joints; elevated alanine aminotransferase; elevated aspartate aminotransferase; steatosis/fatty liver; iron removed by phlebotomy, g; and GNPAT p.D519G positivity. RESULTS: Mean age of 368 participants (73.6% men) was 47 ± 13 (standard deviation) y. Cirrhosis was diagnosed in 86 participants (23.4%). Participants with cirrhosis had significantly greater mean age, proportion of men, diabetes prevalence, mean daily alcohol intake, prevalence of swollen/ tender 2nd/3rd metacarpophalangeal joints, mean serum ferritin, elevated alanine aminotransferase, elevated aspartate aminotransferase, and mean iron removed; and significantly fewer mean blood pints/units donated. GNPAT p.D519G positivity was detected in 82 of 188 participants (43.6%). In a multivariable model for cirrhosis, there were four significant positive associations: age (10-y intervals) (odds ratio 2.2 [95% confidence interval 1.5, 3.3]); diabetes (3.3; [1.1, 9.7]); alcohol intake (14 g alcohol drinks/d) (1.5 [1.2, 1.8]); and iron removed, g (1.3 [1.2, 1.4]). There was no statistical evidence of two-way interactions between these variables. CONCLUSION: In conclusion, cirrhosis in HFE p.C282Y homozygotes is significantly associated with age, diabetes, daily alcohol intake, and iron removed by phlebotomy, taking into account the effect of other variables.

- 174 G>C IL-6 polymorphism and primary iron overload in male patients.

Primary iron overload (IO) is commonly associated with mutations in the hereditary hemochromatosis gene (HFE). Nonetheless, other genetic variants may influence the development of IO beyond HFE mutations. There is a single nucleotide polymorphism (SNP) at - 174 G>C of the interleukin (IL)-6 gene which might be associated with primary IO. Our aim was to study the association between the SNP - 174 G>C gene promoter of IL-6 and primary IO in middle-aged male patients. We studied 37 men with primary IO diagnosed by liver histology. Controls were age-matched male volunteers (n = 37). HFE mutations and the SNP - 174 G>C gene promoter of IL-6 were evaluated by PCR-RFLP. Logistic regression was used to evaluate the association between primary IO and SNP - 174 G>C gene promoter of IL-6. Patients and control subjects were in Hardy-Weinberg equilibrium for the SNP - 174 G>C gene promoter of IL-6 (p = 0.17). Significantly different genotype frequencies were observed between patients (43% CC, 43% CG, and 14% GG) and control subjects (10% CC, 41% CG, and 49% GG) (OR = 4.09, 95% CI = 2.06-8.13; p < 0.0001). The multiple logistic regression analysis showed that IO was significantly associated with CC homozygosis in the SNP - 174 G>C gene promoter of IL-6 (OR = 6.3, 95% CI = 1.9-21.4; p < 0.005) in a model adjusted by age and body mass index. In conclusion, CC homozygosis in the SNP - 174 G>C gene promoter of IL-6 can be proposed as one of the gene variants influencing iron accumulation in male adults with HFE mutations. Studies in larger cohorts are warranted.

Reduced Cerebral White Matter Integrity Assessed by DTI in Cognitively Normal H63D-HFE Polymorphism Carriers.

BACKGROUND AND PURPOSE: The H63D-HFE single nucleotide polymorphism (SNP) has been associated with brain iron dysregulation; however, the emergent role of this missense variant in brain structure and function has yet to be determined. Previous work has demonstrated that HFE SNP carriers have reduced white matter magnetic resonance imaging (MRI) proton relaxation rates. The mechanism by which white matter alterations perturb MRI relaxation is unknown as is how these metrics are related to myelin integrity. METHODS: Fifteen subjects heterozygous for the HFE-H63D SNP and 25 controls with wild-type HFE had diffusion-weighted, anatomical MRIs taken, and underwent cognitive assessment. Fractional anisotropy (FA), mean diffusion (MD), and mode of anisotropy (MO) were calculated from the diffusion dataset to investigate the relationship between the H63D-HFE SNP and myelin integrity. RESULTS: A decrease in FA, an increase in MD, and an increase in MO are demonstrated in multiple H63D-HFE polymorphism carrier white matter tracts. Regions with altered diffusion metrics are notably located in heavily myelinated white matter association fibers, such as the anterior corona radiata and longitudinal fasciculi. CONCLUSIONS: The MRI data presented here demonstrate that H63D-HFE polymorphism carriers have diffusivity changes in white matter compared to wild-type subjects. The reduced integrity white matter tracts in H63D-HFE carriers are hypothesized to be related to increased susceptibility of these late-myelinating regions to cellular stress induced by oligodendrocyte iron dyshomeostasis.

[Iron intake and HFE gen in male adults from Buenos Aires]. / Ingesta de hierro y gen HFE en varones adultos de Buenos Aires.

Excess iron (Fe) intake in subjects carrying certain mutations in the HFE gene may result in Fe overload. To estimate risk of Fe overload, 166 male blood donors (19-65 years) from Buenos Aires city were investigated. Daily Fe intake (FeI), hem Fe intake, and Fe intake from SO4Fe enriched flours were estimated (SARA Computer Program and Food Composition Table, USDA). Serum ferritin and transferrin saturation were determined; criteria for Fe overload was serum ferritin > 300 ng/ml and transferrin saturation = 50%. HFE genotypes C282Y, H63D and S65C were analyzed by PCR-RFLP in blood samples. No participant presented FeI lower than the estimated average requirement (6 mg Fe/day) and 3.0% was over the upper level (45 mg Fe/day). Hem Fe and Fe from flour enrichment were 9.4% and 47.7% of daily Fe intake, respectively. A significant association was observed between the increase in serum ferritin (ng/ml) and the increase in FeI (p = 0.0472); 2.3% of the donors presented serum ferritin > 300 ng/ml and transferrin saturation = 50%. Genotypes associated with hereditary hemochromatosis (H63D, S65C and C282Y) were found in 29.3% of the donors. The percentage of transferrin saturation was higher in subjects carrying mutation than in wild type subjects (p = 0.0167). Although penetrance of hereditary hemochromatosis in the studied group was only 1.2%, an excessive Fe intake could enhance adverse effects in individuals unaware of any family history of Fe overload.

Ingesta de hierro y gen HFE en varones adultos de Buenos Aires / Iron intake and HFE gen in male adults from Buenos Aires

El consumo excesivo de hierro (Fe) en portadores de mutaciones en el gen HFE puede resultar en sobrecarga. Para evaluar el riesgo de sobrecarga de Fe fueron investigados 166 varones adultos donantes de sangre de la ciudad de Buenos Aires. Se estimó la ingesta diaria de Fe (IFe), de Fe hemínico y de Fe proveniente de harinas enriquecidas con SO4Fe. Se determinó ferritina sérica y porcentaje de saturación de transferrina (criterio de sobrecarga de Fe: ferritina sérica > 300 ng/ml y saturación de transferrina ≥ 50%). Las mutaciones C282Y, H63D y S65C fueron investigadas en sangre mediante PCR-RFLP. Todos los participantes cubrieron ampliamente el requerimiento estimado promedio de Fe (6 mg Fe/día) y 3.0% superó el máximo tolerable (45 mg Fe/día). El Fe hemínico correspondió al 9.4% de la IFe y el de harinas enriquecidas al 47.7%. Se observó una asociación entre el aumento de IFe y el de ferritina sérica (p = 0.0472), y el 2.3% de los donantes presentaron ferritina sérica > 300 ng/ml y saturación de transferrina ≥ 50%. El 29.3% de los donantes eran portadores de los genotipos H63D, S65C o C282Y, asociados a hemocromatosis hereditaria, y tenían valores de saturación de transferrina significativamente mayores a los de los donantes wild type (p = 0.0167). Si bien la incidencia clínica de hemocromatosis hereditaria fue baja en el grupo estudiado (1.2%), el consumo excesivo de Fe plantea un riesgo potencial para la salud de individuos que ignoran sus antecedentes familiares de sobrecarga de Fe.

Excess iron (Fe) intake in subjects carrying certain mutations in the HFE gene may result in Fe overload. To estimate risk of Fe overload, 166 male blood donors (19-65 years) from Buenos Aires city were investigated. Daily Fe intake (FeI), hem Fe intake, and Fe intake from SO4Fe enriched flours were estimated (SARA Computer Program and Food Composition Table, USDA). Serum ferritin and transferrin saturation were determined; criteria for Fe overload was serum ferritin > 300 ng/ml and transferrin saturation ≥ 50%. HFE genotypes C282Y, H63D and S65C were analyzed by PCR-RFLP in blood samples. No participant presented FeI lower than the estimated average requirement (6 mg Fe/day) and 3.0% was over the upper level (45 mg Fe/day). Hem Fe and Fe from flour enrichment were 9.4% and 47.7% of daily Fe intake, respectively. A significant association was observed between the increase in serum ferritin (ng/ml) and the increase in FeI (p = 0.0472); 2.3% of the donors presented serum ferritin > 300 ng/ml and transferrin saturation ≥ 50%. Genotypes associated with hereditary hemochromatosis (H63D, S65C and C282Y) were found in 29.3% of the donors. The percentage of transferrin saturation was higher in subjects carrying mutation than in wild type subjects (p = 0.0167). Although penetrance of hereditary hemochromatosis in the studied group was only 1.2%, an excessive Fe intake could enhance adverse effects in individuals unaware of any family history of Fe overload.

HFE gene polymorphism defined by sequence-based typing of the Brazilian population and a standardized nomenclature for HFE allele sequences.

The HFE molecule controls iron uptake from gut, and defects in the molecule have been associated with iron overload, particularly in hereditary hemochromatosis. The HFE gene including both coding and boundary intronic regions were sequenced in 304 Brazilian individuals, encompassing healthy individuals and patients exhibiting hereditary or acquired iron overload. Six sites of variation were detected: (1) H63D C>G in exon 2, (2) IVS2 (+4) T>C in intron 2, (3) a C>G transversion in intron 3, (4) C282Y G>A in exon 4, (5) IVS4 (-44) T>C in intron 4, and (6) a new guanine deletion (G>del) in intron 5, which were used for haplotype inference. Nine HFE alleles were detected and six of these were officially named on the basis of the HLA Nomenclature, defined by the World Health Organization (WHO) Nomenclature Committee for Factors of the HLA System, and published via the IPD-IMGT/HLA website. Four alleles, HFE*001, *002, *003, and *004 exhibited variation within their exon sequences.

GNPAT rs11558492 is not a Major Modifier of Iron Status: Study of Italian Hemochromatosis Patients and Blood Donors.

BACKGROUND AND AIM: HFE-related Hemochromatosis (HH) is characterized by marked phenotype heterogeneity, probably due to the combined action of acquired and genetic factors. Among them, GNPAT rs11558492 was proposed as genetic modifier of iron status, but results are still controversial. To shed light on these discrepancies, we genotyped 298 Italian p.C282Y homozygotes and 169 healthy controls. MATERIAL AND METHODS: Allele and genotype frequencies were analysed and compared with those reported in Exome Variant Server (EVS). To explore the role of rs11558492 as a potential modifier of iron status, serum ferritin (SF), liver iron concentration (LIC) and iron removed (IR) were studied according to allele and genotype frequencies. In addition, the effect of the SNP on liver fibrosis was examined comparing patients with absent/mild-moderate fibrosis to those with severe fibrosis-cirrhosis. RESULTS: GNPAT rs11558492 minor allele (G) frequency (MAF) was 20.3% in HFE-HH, 17.2% in controls and 20.6% in EVS database. Genotype frequencies were 64% and 69.2% (AA), 31.2% and 27.2% (AG), 4.8% and 3.6% (GG) in HFE-HH and controls, respectively. No significant differences were found comparing genotype and allele frequencies even selecting subgroups of only-males with extreme phenotypes and low alcohol intake. SF, IR and LIC levels did not significantly differ according to rs11558492 genotypes. Also, MAF did not differ between patients with absent/mild fibrosis and severe fibrosis/cirrhosis. CONCLUSIONS: Our findings indicate that GNPAT rs11558492 is not a major modifier of iron status and is not associated with liver fibrosis in HFE-HH patients.