C282Y Homozygosity Research Articles

Screening for C282Y homozygosity in a Norwegian population (HUNT2): The sensitivity and specificity of transferrin saturation

Objective. Hereditary hemochromatosis (HH) is a genetic condition characterized by increased iron absorption. Most HH cases are homozygous for the C282Y mutation in the HFE gene, but accurate prevalence data for the Norwegian population is lacking. In population studies, serum transferrin saturation (TS) is commonly used as a screening test. However, the sensitivity and specificity of TS in this setting is not well documented. The purpose of this study was to determine the prevalence of the C282Y mutation in the general population, and to evaluate the diagnostic accuracy of the TS test as a screening criterion for finding C282Y homozygotes. Materials and methods. The hemochromatosis screening study in Nord-Trøndelag county, Norway (the HUNT2 study) comprised 65,238 participants. The HUNT biobank contains biological material and data from the participants, and 5000 individuals were randomly selected. Genotyping of the common HFE gene mutations was successful for 4827 samples, from which TS data existed for 4804 individuals. From these data we calculated the population frequency of the C282Y mutation, and the sensitivity and specificity of TS measurements. Results. The prevalence of C282Y homozygosity in the population was 0.75%. Using 55% (men) and 50% (women) as decision limits, the sensitivity of two consecutive elevated TS measurements was 90.0% for men and 55.0% for women, whereas the specificity was 99.6% and 99.4%, respectively. Conclusion. An unbiased estimate of the C282Y homozygote prevalence in Norway is 0.75%. Two measurements of TS is an accurate screening test for C282Y homozygosity in men, but not in women.

Phlebotomies as a treatment of serious heart failure due to haemochromatosis: a case report.

Haemochromatosis is a disturbance in the iron metabolism leading to excessive accumulation of iron in various organs such as the liver, pancreas, joints, skin, pituitary, testes and heart, with the last mentioned leading to heart failure. In this report we describe a patient with serious heart failure, attributed to homozygosity for C282Y in the haemochromatosis (HFE) gene, in whom repetitive phlebotomies led to normalisation of left ventricular function. (Neth Heart J 2009;17:438-41.).

Does Oxidative Stress Modulate Left Ventricular Diastolic Function in Asymptomatic Subjects with Hereditary Hemochromatosis?

Little is known about the early mechanisms mediating left ventricular (LV) diastolic dysfunction in patients with hereditary hemochromatosis (HH). However, the increased oxidative stress related to iron overload may be involved in this process, and strain rate (SR), a sensitive echocardiography-derived measure of diastolic function, may detect such changes. we evaluated the relationship between left ventricular diastolic function measured with tissue Doppler SR and oxidative stress in asymptomatic HH subjects and control normal subjects. Ninety-four consecutive visits of 43 HH subjects, age 30-74 (50 +/- 10, mean +/- SD), and 37 consecutive visits of 21 normal volunteers, age 30-63 (48 +/- 8), were evaluated over a 3-year period. SR was obtained from the basal septum in apical four-chamber views. All patients had confirmed C282Y homozygosity, a documented history of iron overload, and were New York Heart Association functional class I. Normal volunteers lacked HFE gene mutations causing HH. In the HH subjects, the SR demonstrated moderate but significant correlations with biomarkers of oxidative stress; however, no correlations were noted in normal subjects. The biomarkers of iron overload per se did not show significant correlations with the SR. Although our study was limited by the relatively small subject number, these results suggest that a possible role of oxidative stress to affect LV diastolic function in asymptomatic HH subjects and SR imaging may be a sensitive measure to detect that effect.

Letter by Sullivan Regarding Article, “HFE C282Y Homozygosity Is Associated With Lower Total and Low-Density Lipoprotein Cholesterol: the Hemochromatosis and Iron Overload Screening Study”

To the Editor: Adams et al1 report lower serum cholesterol and low-density lipoprotein levels in hemochromatosis patients homozygous for C282Y. They suggest a role for excess iron in this effect; however, ironically, an alternative mechanism may involve a relative lack of intracellular iron in certain cell types in homozygous patients. The classical finding of parenchymal iron loading …

Diagnostic strategies using DNA testing for hereditary haemochromatosis in at-risk populations: a systematic review and economic evaluation

To evaluate DNA testing for detecting hereditary haemochromatosis (HHC) in subgroups of patients suspected of having the disorder and in family members of those diagnosed with HHC. Major electronic databases, searched from inception to April 2007. A systematic review was undertaken using a priori methods and a de novo model developed to assess costs and consequences of DNA testing. Eleven studies were identified for estimating the clinical validity of genotyping for the C282Y mutation for the diagnosis of HHC. No clinical effectiveness studies meeting the inclusion criteria were identified. Two North American cost-effectiveness studies of reasonable quality were identified but their generalisability to the UK is not clear. Three cohort studies met the inclusion criteria for the review of psychosocial aspects. All had methodological limitations and their generalisability is difficult to determine. The clinical sensitivity of C282Y homozygosity for HHC ranged from 28.4% to 100%, or from 91.3% to 92.4% when considering only the most relevant studies. Clinical specificity ranged from 98.8% to 100%. One study found that gene testing was a cost-effective method of screening relatives of patients with haemochromatosis, whereas the other found that genotyping the spouse of a homozygote was the most cost-efficient strategy. Genetic testing for haemochromatosis appears to be well accepted, is accompanied by few negative psychosocial outcomes and may lead to reduced anxiety. The de novo economic model showed that, in people suspected of having haemochromatosis, the DNA strategy is cost saving compared with the baseline strategy using liver biopsy (cost saved per case detected 123 pounds), largely because of the reduction in liver biopsies. For family testing of siblings the DNA strategy is not cost saving because of the costs of the DNA test (additional cost per case detected 200 pounds). If the cost of the test were to reduce from 100 pounds to 60 pounds, the DNA strategy would be the cheaper one. For family testing of offspring the DNA test strategy is cheaper than the baseline biochemical testing strategy (cost saved per case detected 7982 pounds). Sensitivity analyses showed that the conclusions in each case are robust across all reasonable parameter values. The preferred strategy in practice is DNA testing in conjunction with testing iron parameters when there is clear clinical indication of risk for haemochromatosis because of biochemical criteria or when there is familial risk for HHC. Access to genetic testing and centralisation of test provision in expert laboratories would lower the cost of testing, improve the cost-effectiveness of the strategy and improve the quality of information provided to clinicians and patients.

Haemochromatosis HFE gene polymorphisms as potential modifiers of hereditary nonpolyposis colorectal cancer risk and onset age

Hereditary nonpolyposis colorectal cancer (HNPCC) is characterized by germline mutations in DNA mismatch repair genes; however, variation in disease expression suggests that there are potential modifying factors. Polymorphisms of the HFE gene, which cause the iron overload disorder hereditary haemochromatosis, have been proposed as potential risk factors for the development of colorectal cancer (CRC). To understand the relationship between HNPCC disease phenotype and polymorphisms of the HFE gene, a total of 362 individuals from Australia and Poland with confirmed causative MMR gene mutations were genotyped for the HFE C282Y and H63D polymorphisms. A significantly increased risk of developing CRC was observed for H63D homozygotes when compared with combined wild-type homozygotes and heterozygotes (hazard ratio = 2.93, p = 0.007). Evidence for earlier CRC onset was also observed in H63D homozygotes with a median age of onset 6 years earlier than wild type or heterozygous participants (44 vs. 50 years of age). This effect was significant by all tests used (log-rank test p = 0.026, Wilcoxon p = 0.044, Tarone-Ware p = 0.035). No association was identified for heterozygosity of either polymorphism and limitations on power-prevented investigation of C282Y homozygosity or compound C282Y/H63D heterozygosity. In the Australian sample only, women had a significantly reduced risk of developing CRC when compared with men (hazard ratio = 0.58, p = 0.012) independent of HFE genotype for either single nucleotide polymorphisms. In conclusion, homozygosity for the HFE H63D polymorphism seems to be a genetic modifier of disease expression in HNPCC. Understanding the mechanisms by which HFE interrelates with colorectal malignancies could lead to reduction of disease risk in HNPCC.

HFE C282Y Homozygosity Is Associated With Lower Total and Low-Density Lipoprotein Cholesterol

Background— Previous studies have suggested a positive association of coronary heart disease risk and both serum ferritin concentrations and C282Y heterozygosity. Relationships between serum lipids, C282Y homozygosity, and serum ferritin have not been well established. Methods and Results— The Hemochromatosis and Iron Overload Screening study screened 101 168 participants in primary care from 5 field centers in the United States and Canada with serum ferritin, transferrin saturation, and HFE genotyping for C282Y and H63D mutations. Serum lipids were measured in a subset of 176 C282Y homozygotes (63 male, 113 female whites) without a prior diagnosis of, family history, or treatment for hemochromatosis and a matched sample of participants with normal transferrin saturation and serum ferritin without C282Y or H63D mutations (wild-type, 123 male, 189 female whites). The proportion of subjects who reported using prescription cholesterol-lowering medications was ≈3 times higher in HFE wild-type subjects than C282Y homozygotes among men (22% versus 7%; P =0.02) and, in women, 2 times higher (16% versus 8%; P =0.07). After excluding subjects taking cholesterol medications, C282Y homozygotes had significantly lower mean total and low-density lipoprotein cholesterol concentrations than wild-type subjects, with larger genotypic differences for low-density lipoprotein in men (−0.62 mmol/L; 95% CI, −0.93 to −0.33) than in women (−0.28 mmol/L; 95%, CI −0.52 to −0.08). Conclusions— Total mean serum cholesterol and low-density lipoprotein levels were lower in C282Y homozygotes than in HFE wild-type participants. Further studies are required to determine whether this is related to iron overload, HFE alleles, or other factors on C282Y-positive chromosome 6p haplotypes.

Screening for iron overload: lessons from the hemochromatosis and iron overload screening (HEIRS) study.

The HEmochromatosis and IRon Overload Screening (HEIRS) Study provided data on a racially, ethnically and geographically diverse cohort of participants in North America screened from primary care populations. A total of 101,168 participants were screened by testing for HFE C282Y and H63D mutations, and measuring serum ferritin concentration and transferrin saturation. In the present review, lessons from the HEIRS Study are highlighted in the context of the principles of screening for a medical disease as previously outlined by the World Health Organization. Genetic testing is well accepted, with minimal risk of discrimination. Transferrin saturation has high biological variability and relatively low sensitivity to detect HFE C282Y homozygotes, which limits its role as a screening test. Symptoms attributable to HFE C282Y homozygosity are no more common in individuals identified by population screening than in control subjects. Generalized population screening in a primary care population as performed in the HEIRS Study is not recommended. There may be a role for focused screening in Caucasian men, with some debate regarding genotyping followed by phenotyping, or phenotyping followed by genotyping.

Coinheritance of hereditary spherocytosis and reversibility of cirrhosis in a young female patient with hereditary hemochromatosis

Here we report a 33-years-old woman with hereditary spherocytosis and hemochromatosis due to homozygosity for the C282Y mutation of the HFE gene. The coinheritance of both conditions led to severe iron overload and liver cirrhosis at young age. The patient was treated by repeated phlebotomy, and reversibility of cirrhosis was documented by transient elastography. This report discusses the pathophysiology of iron accumulation in patients with hemolytic anemia combined with HFE C282Y homozygosity. The case indicates that patients with hematological disorders characterized by increased erythropoetic activity should be screened for HFE mutations.

Hereditary hemochromatosis: insights from the Hemochromatosis and Iron Overload Screening (HEIRS) Study.

Hemochromatosis comprises a group of inherited disorders resulting from mutations of genes involved in regulating iron metabolism. The multicenter, multi-ethnic Hemochromatosis and Iron Overload Screening (HEIRS) Study screened approximately 100,000 participants in the US and Canada, testing for HFE mutations, serum ferritin and transferrin saturation. As in other studies, HFE C282Y homozygosity was common in Caucasians but rare in other ethnic groups, and there was a marked heterogeneity of disease expression in C282Y homozygotes. Nevertheless, this genotype was often associated with elevations of serum ferritin and transferrin saturation and with iron stores of more than four grams in men but not in women. If liver biopsy was performed, in some cases because of evidence of hepatic dysfunction, fibrosis or cirrhosis was often found. Combined elevations of serum ferritin and transferrin saturation were observed in non-C282Y homozygotes of all ethnic groups, most prominently Asians, but not often with iron stores of more than four grams. Future studies to discover modifier genes that affect phenotypic expression in C282Y hemochromatosis should help identify patients who are at greatest risk of developing iron overload and who may benefit from continued monitoring of iron status to detect progressive iron loading.

Predicting Iron Overload in Hyperferritinemia

Hyperferritinemia is a common abnormality. This study determined the prevalence of hepatic iron overload in subjects of northern European origin with hyperferritinemia. Fifty-two consecutive subjects referred for evaluation of suspected iron overload (serum ferritin level >350 microg/L) were divided into 3 groups: group 1, increased transferrin saturation and no significant hemochromatosis gene product (HFE) mutations (N = 17); group 2, increased transferrin saturation and C282Y homozygosity or C282Y/H63D compound heterozygosity (N = 22); and group 3, normal transferrin saturation and no significant HFE mutations (N = 13). All subjects underwent magnetic resonance R2 relaxometry for quantitation of hepatic iron concentration (HIC). The HIC was significantly higher in group 2 subjects (123 +/- 22 micromol/g) compared with groups 1 and 3 subjects (39 +/- 4 and 36 +/- 5 micromol/g, respectively) (P < .01). Nine of 22 subjects in group 2 had an increase of their HIC to greater than 3 times the upper limit of normal compared with none in the other 2 groups (P < .01). An increase of HIC to greater than 3 times the upper limit of normal is highly unlikely in hyperferritinemic subjects who do not have HFE-related hereditary hemochromatosis or causes of secondary iron overload.

Haemochromatosis gene frequency in a control and diabetic Irish population

Hereditary haemochromatosis is inherited in an autosomal recessive manner. Two major mutations have been identified and the condition is emerging as one of the most common recessive mutations among subjects of Northern European descendants. This study investigated the prevalence of C282Y, H63D and S65C (three mutations of clinical significance for haemochromatosis), in a diabetic and control population from the North West of Ireland. DNA was extracted from whole blood samples of 249 known diabetics and 249 controls and assayed for the three genetic variants (C282Y, H63D and S65C). The incidence for C282Y homozygosity is higher in the control population (1 in 83) when compared to the diabetic group (1 in 249). However, this is not statistically significant. S65C heterozygosity occurs with an incidence of 1 in 32 in control individuals and 1 in 124 in the diabetic population. The prevalence of the H63D mutation was similar in both populations. For the three haemochromatosis mutations, there was no significant difference between the control group and the diabetic populations.

Severity of iron overload of proband determines serum ferritin levels in families with HFE-related hemochromatosis: The HEmochromatosis FAmily Study

In families of patients with clinically detected hereditary hemochromatosis (HH) early screening has been suggested to prevent morbidity and mortality. Here, we aim to identify determinants for iron overload in first-degree family members of C282Y homozygous probands with clinically detected HH. Data on HFE-genotype, iron parameters, demographics, lifestyle factors and health, were collected from 224 Dutch C282Y homozygous patients with clinically diagnosed HH and 735 of their first-degree family members (FDFM), all participating in the HEmochromatosis FAmily Study (HEFAS). The best predictive multivariable model forecasted 45% of variation of the serum ferritin levels. In this model severity of iron overload in the proband significantly predicted serum ferritin levels in FDFM. Other significant determinants in this model consisted of C282Y homozygosity, compound heterozygosity, age at testing for serum ferritin and supplemental iron intake, whereas a low body mass index showed a protective effect. This study provides a model to assess the risk of development of iron overload for relatives of probands with HH. These results might be instrumental in the development of an optimal strategy for future family screening programs.

The Natural History of Serum Iron Indices for HFE C282Y Homozygosity Associated With Hereditary Hemochromatosis

There are few longitudinal studies of serum ferritin (SF) and transferrin saturation (TS) levels in individuals homozygous for the C282Y mutation. We characterized the development of elevated iron measures in C282Y homozygotes followed for 12 years. From 31,192 people aged 40-69 years at baseline, we identified 203 C282Y homozygotes (95 males), of whom 116 had SF and fasting TS levels measured at baseline (mean age, 55 years) and 86 were untreated and had iron measures at follow-up (mean, 12 years later). The probabilities of SF at follow-up exceeding clinical thresholds were predicted from baseline SF and TS under a multivariate normal model. For C282Y homozygotes, at baseline, 84% of males and 65% of females had elevated SF and 37% of males and 3% of females had SF >1000 microg/L. For males with SF 300-1000 microg/L at baseline, the predicted probability of progressing to SF >1000 microg/L at follow-up was between 13% and 35% and, for females, between 16% and 22%. For C282Y homozygotes with normal baseline SF, <15% were predicted to develop SF >1000 microg/L if left untreated. The majority of C282Y homozygotes who are likely to develop SF levels sufficient to place them at risk of iron overload-related disease will have done so by mean age 55 years. TS >95% at mean age 55 years in males increases the likelihood that SF levels will be elevated at mean age 65 years, but this effect is absent in females, most likely because of physiologic blood loss associated with menstruation.

Non-classical hereditary hemochromatosis in Portugal: novel mutations identified in iron metabolism-related genes

The most frequent genotype associated with Hereditary hemochromatosis is the homozygosity for C282Y, a common HFE mutation. However, other mutations in HFE, transferrin receptor 2 (TFR2), hemojuvelin (HJV) and hepcidin (HAMP) genes, have also been reported in association with this pathology. A mutational analysis of these genes was carried out in 215 Portuguese iron-overloaded individuals previously characterized as non-C282Y or non-H63D homozygous and non-compound heterozygous. The aim was to determine the influence of these genes in the development of iron overload phenotypes in our population. Regarding HFE, some known mutations were found, as S65C and E277K. In addition, three novel missense mutations (L46W, D129N and Y230F) and one nonsense mutation (Y138X) were identified. In TFR2, besides the I238M polymorphism and the rare IVS5 -9T-->A mutation, a novel missense mutation was detected (F280L). Concerning HAMP, the deleterious mutation 5'UTR -25G-->A was found once, associated with Juvenile Hemochromatosis. In HJV, the A310G polymorphism, the novel E275E silent alteration and the novel putative splicing mutation (IVS2 +395C-->G) were identified. In conclusion, only a few number of mutations which can be linked to iron overload was found, revealing their modest contribution for the development of this phenotype in our population, and suggesting that their screening in routine diagnosis is not cost-effective.

Thyroid-Stimulating Hormone and Free Thyroxine Levels in Persons with HFE C282Y Homozygosity, a Common Hemochromatosis Genotype: The HEIRS Study

Relationships of thyroid and iron measures in large cohorts are unreported. We evaluated thyroid-stimulating hormone (TSH) and free thyroxine (T4) in white participants of the primary care-based Hemochromatosis and Iron Overload Screening (HEIRS) Study. We measured serum TSH and free T4 in 176 HFE C282Y homozygotes without previous hemochromatosis diagnoses and in 312 controls without HFE C282Y or H63D who had normal serum iron measures and were matched to C282Y homozygotes for Field Center, age group, and initial screening date. We defined hypothyroidism as having TSH >5.00 mIU/L and free T4 <0.70 ng/dL, and hyperthyroidism as having TSH <0.400 mIU/L and free T4 >1.85 ng/dL. Multivariate analyses were performed using age, sex, Field Center, log(10) serum ferritin (SF), HFE genotype, log(10) TSH, and log(10) free T4. Prevalences of hypothyroidism in C282Y homozygotes and controls were 1.7% and 1.3%, respectively, and of hyperthyroidism 0% and 1.0%, respectively. Corresponding prevalences did not differ significantly. Correlations of log(10) SF with log(10) free T4 were positive (p = 0.2368, C282Y homozygotes; p = 0.0492, controls). Independent predictors of log(10) free T4 were log(10) TSH (negative association) and age (positive association); positive predictors of log(10) SF were age, male sex, and C282Y homozygosity. Proportions of C282Y homozygotes and controls who took medications to supplement or suppress thyroid function did not differ significantly. Prevalences of hypothyroidism and hyperthyroidism are similar in C282Y homozygotes without previous hemochromatosis diagnoses and controls. In controls, there is a significant positive association of SF with free T4. We conclude that there is no rationale for routine measurement of TSH or free T4 levels in hemochromatosis or iron overload screening programs.

Modifying factors of the HFE hemochromatosis phenotype

C282Y homozygosity is the only common HFE genotype able to produce a complete hemochromatosis phenotype. However, its biochemical penetrance is incomplete (75% in men and 50% in women) and its clinical penetrance is low, especially in women (1 vs 25% in men). Environmental (e.g., diet, alcohol, drugs and metabolic syndrome) and genetic (digenism, common polymorphisms in the bone morphogenetic protein pathway involved in the regulation of hepcidin synthesis) explain a part of the variability of the C282Y homozygous phenotype. All other common HFE genotypes – including C282Y–H63D compound heterozygosity – are not associated with significant biochemical and clinical expression in the absence of comorbid factors (e.g., alcohol, diabetes or steatohepatitis). Better identification of acquired and genetic modifiers of iron burden and iron-related organ damage is needed to improve the preventive, diagnostic and therapeutic management of HFE hemochromatosis.

HFE C282Y homozygotes have reduced low-density lipoprotein cholesterol: the Atherosclerosis Risk in Communities (ARIC) Study

Recent studies have raised questions about the long-term health risks for individuals with mutations in the <i>HFE</i> gene, although previous studies may have been plagued by selection bias or lack of population-based comparison groups. We examined cardiovascular disease risk factors and iron and liver biomarkers, as well as morbidity and mortality associated with the C282Y and H63D variants of <i>HFE</i> in the Atherosclerosis Risk in Communities (ARIC) study, which is a population-based cohort of nearly 16,000 U.S. white and black men and women who were 45–64 years old at baseline. Subjects were followed for an average of 15 years for death, incident coronary heart disease, stroke, and heart failure, and an average of 8 years for incident diabetes. The prevalence of C282Y homozygosity was 0.42% (45/10,800) in whites, which is similar to other North American population-based studies. C282Y homozygotes had significantly lower mean low-density lipoprotein (LDL) cholesterol and fibrinogen as well as higher mean levels of iron (ferritin, transferrin saturation) and liver biomarkers (alanine aminotransferase, Hepascore) compared with <i>HFE</i> wild-type subjects. Rates of all-cause mortality, cardiovascular disease, and diabetes were similar across <i>HFE</i> genotypes. These prospective, population-based data indicate higher serum iron indices and possible mild liver dysfunction or disease in some C282Y homozygotes, but they provide little evidence that <i>HFE</i> C282Y or H63D mutations are related to all-cause mortality, cardiovascular disease, or diabetes. Reduced LDL in C282Y homozygotes may be because of effects of excess iron on cholesterol metabolism and lipoprotein formation in the liver.

Ferritin >1000: grand for hemochromatosis screening?

In this issue of Blood , Waalen and colleagues describe one-time screening using serum ferritin (SF) greater than 1000 μg/L to detect HFE hemochromatosis and increased risk of cirrhosis in non-Hispanic white individuals. HFE C282Y homozygosity occurs in 0.44% to 0.48% of non-Hispanic white

Distribution of HFE gene mutations in Slovenian patients with hereditary hemochromatosis

Dear Editor, Hereditary hemochromatosis (HH; HFE-related or type 1 genetic hemochromatosis) is a common autosomal recessive disorder of iron metabolism, its prevalence being two to five per 1,000 in Caucasians, characterized by increased iron absorption and progressive iron storage, resulting in organ damage, especially liver cirrhosis. Because the clinical consequences can be prevented by repeated phlebotomies, early accurate diagnosis is crucial. This can be achieved by genetic testing. By this approach, HH becomes a preventable genetic disorder on secondary level. In the hemochromatosis gene (HFE), two missense mutations were initially identified: C282Y (c.845G>A/p. C282Y) and H63D (c.187C>G/ p.H63D), followed by a third mutation: S65C (c.193A>T/p.S65C) [3, 10]. In European populations, the estimated contribution of C282Y homozygosity to the HH phenotype is up to 96%. The prevalence decreases from northern to southern Europe. The H63D mutation has a frequency of approximately 16% in the European populations, the proportion of the compound C282Y/H63D heterozygotes among HH patients being the highest in southern Europe. The S65C mutation accounts for approximately 8% of HH chromosomes, which are neither C282Y nor H63D [4, 6, 7, 10]. Reports on the prevalence of HFE mutations in HH patients in Slavic populations are scarce. The present study was performed in order to establish the frequencies of the three HFE mutations in Slovenian HH patients. Forty-nine unrelated HH patients of Slovenian origin were ascertained through the Registry at the Gastroenterology Department, University Medical Center Ljubljana, Slovenia (mean age 48 years, age range 22–69 years): there were 39 men and ten women. In all patients included in the study, the clinical diagnosis of HH was established based on the following criteria: increased transferrin saturation (TS): >50% for females and >60% for males; increased serum ferritin: >200 μg/l for females and >400 μg/l for males. Iron serum markers were measured by standard methods. In 47 of the 49 patients, HH diagnosis and staging was confirmed by liver biopsy and iron staining. Hepatic iron index was not calculated. In two patients who refused liver biopsy, liver iron overload was established by magnetic resonance imaging. Exclusion criteria were: alcohol abuse, secondary iron overload and antihepatitis C and B virus positivity. The study was approved by the National Medical Ethics Committee. Informed consent was obtained from all patients. The analysis of the HFE gene mutations was performed using polymerase chain reaction [3, 10]. The mutation analysis of 49 HH patients revealed that 35 (71.4%) were homozygous for C282Y mutation, and two patients (4.1%) were C282Y–H63D compound heterozygotes. Thus, the C282Y mutation was present in 37 of the 49 patients (75.5%). Among the 12 patients without the C282Y mutation, one (2%) was H63D–S65C compound heterozygote, five (10.2%) Ann Hematol (2008) 87:667–669 DOI 10.1007/s00277-008-0463-2