Genetic screening for HFE hemochromatosis in 6,020 Danish men: penetrance of C282Y, H63D, and S65C variants

The aim of this epidemiologic population survey was to assess the penetrance of the most frequent hemochromatosis (HFE) gene variants in ethnic Danish men. A cohort of 6,020 men aged 30–53 years was screened for HFE C282Y, H63D, and S65C variants by restriction fragment length polymorphism analysis. Subsequently, iron status markers (serum transferrin saturation, serum ferritin) were analyzed in 1,452 men. The C282Y allele was present in 5.6%, H63D in 12.8%, and S65C in 1.8% of the men. We found 23 out of 6,020 (0.38%) C282Y homozygotes, of whom two had been treated with phlebotomy. Among untreated C282Y homozygotes (n = 21) with available iron status markers (transferrin saturation n = 18, ferritin n = 16), 89% had elevated transferrin saturation ≥50%, 94% had elevated ferritin ≥300 μg/L, and 88% had elevation of both iron status markers; seven out of 16 (44%) had ferritin values >800 μg/L. One C282Y homozygote had normal iron status markers possibly due to nonexpressivity. Among C282Y/H63D compound heterozygotes (n = 66), 23% had elevated transferrin saturation, 27% elevated ferritin, and 9% elevation of both iron status markers. Among H63D/H63D homozygotes (n = 74), 15% had elevated transferrin saturation, 19% elevated ferritin, and 5.4% elevation of both iron status markers. Among C282Y/wild type (wt) heterozygotes (n = 255), 9% had elevated transferrin saturation, 9% elevated ferritin, and 1.2% elevation of both iron status markers. Among H63D/wt heterozygotes (n = 600), 8% had elevated transferrin saturation, 12% elevated ferritin, and 2% elevation of both iron status markers. None of the men with the S65C variant displayed elevation of both iron status markers. In conclusion, this study demonstrates a high penetrance of the C282Y variant in Danish men followed by the H63D variant while the S65D variant had no significant impact on iron status markers.     

Frequency of the hemochromatosis HFE mutations C282Y, H63D, and S65C in blood donors in the Faroe Islands

The aim of the study was to assess the frequencies of the hereditary hemochromatosis HFE mutations C282Y, H63D, and S65C in the population in the Faroe Islands. The series comprised 200 randomly selected blood donors of Faroese heritage. The frequency of the C282Y, H63D, and S65C mutations on the HFE gene was assessed by genotyping using the polymerase chain reaction (PCR) technique and calculated from direct allele counting. We found no C282Y homozygous subjects; 28 (14.0%) subjects were C282Y heterozygous and four subjects were C282Y/H63D compound heterozygous (2.0%). The C282Y allele frequency was 8.0% (95% CI 5.3–10.7%). The series contained three (1.5%) H63D homozygous subjects and 60 (30.0%) H63D heterozygous subjects. The H63D allele frequency was 17.5% (95% CI 13.8–21.2%). There were four (2.0%) S65C heterozygous subjects. The S65C allele frequency was 1.0% (95% CI 0.3–2.5%). The frequency of the C282Y mutation is high in Faroese blood donors, being close to and not significantly different from the frequencies reported in other Scandinavian countries: Denmark 5.7%, Norway 6.6%, Iceland 5.1%, and Sweden 6.1%. The frequency of the H63D mutation in Faroese subjects is significantly higher than the frequency in Denmark 12.8% (p=0.007), Iceland 10.9% (p=0.003), and Sweden 12.4% (p=0.015), but not from the frequency in Norway 11.2% (p=0.063). The frequency of the S65C mutation in Faroese subjects is not significantly different from the frequencies in Denmark 1.5% and Sweden 1.6%. Screening of larger groups of the Faroese population for HFE mutations especially C282Y should be considered in order to establish the penetrance.     

Frequencies of the haemochromatosis gene (<Emphasis Type="Italic">HFE</Emphasis>) variants C282Y,H63D and S65C in 6,020 ethnic Danish men

The objective was to assess the frequencies of haemochromatosis (HFE) gene mutations or variants C282Y, H63D and S65C in ethnic Danes. This is a prospective epidemiologic population study. A cohort of 6,020 Danish men aged 30-50 years was screened for HFE C282Y (c845G-->A), H63D (c187C-->G) and S65C (c193A-->T) gene variants, assessed on saliva or blood samples by restriction fragment length polymorphism (RFLP) analysis. The C282Y gene variant allele was present in 5.6%, H63D in 12.8% and S65C in 1.8% of the chromosomes. In the entire series, we observed 1.4% H63D/C282Y, 0.1% S65C/C282Y and 0.4% H63D/S65C compound heterozygotes. The C282Y allele frequency in Denmark is of similar order as reported in other Scandinavian countries: Iceland 5.1%, Faeroe Islands 6.6%, Norway 6.8% and Sweden 5.8%. Also, the H63D frequency in Denmark is close to the frequencies in other Scandinavian countries: Iceland 10.9%, Faeroe Islands 15.2%, Norway 11.4% and Sweden 12.1%.     

Frequency of the C282Y and H63D mutations of the hemochromatosis gene (HFE) in 2501 ethnic Danes

The aim of the study was to assess the frequency of the C282Y and H63D mutations of the hemochromatosis gene (HFE) in ethnic Danes. The series comprised 2501 subjects (1284 men) of Danish heritage who were drawn at random from the Census Registry in age cohorts of 30, 40, 50, and 60 years. The frequency of the C282Y and H63D mutations was assessed on blood samples by genotyping using a polymerase chain reaction (PCR) technique. The HFE genotype distribution was in Hardy–Weinberg equilibrium (p=0.85). C282Y mutation: 9 subjects (0.36%) were homozygous and 265 subjects (10.6%) were heterozygous. H63D mutation: 40 subjects (1.6%) were homozygous and 584 subjects (23.4%) were heterozygous. C282Y/H63D compound heterozygosity was found in 36 subjects (1.4%). The C282Y allele frequency was 5.7% [95% confidence interval (CI) 5.0–6.3%] and the H63D allele frequency was 13.3% (95% CI 12.3–14.2%). In conclusion, the C282Y frequency is relatively high in the Danes, being close to the frequency in other Scandinavian countries, i.e., Iceland 5.1%, the Faroe Islands 6.6%, and Sweden 5.7%, but significantly lower than in Norway 6.6% (p=0.02). Also, the H63D frequency in Danes is close to and not significantly different from the frequency in Iceland 10.9%, Norway 11.2%, and Sweden 12.4%, but significantly lower than in the Faroe Islands 15.4% (p=0.046).     

Compound Heterozygote (C282Y/H63D) of Hereditary Hemochromatosis in a 16-Year-Old Girl with Hypoplastic Kidney

Iron-overload diseases are associated with primary or secondary disturbances of iron metabolism. Hereditary hemochromatosis, a genetically heterogeneous disease that is characterized by increased iron absorption and progressive deposition in parenchymal cells, may lead to organ damage and failure. Molecular studies have shown that hemochromatosis type 1 is predominantly due to a mutation in the HFE gene; there are 2 major mutations (C282Y and H63D). Disease symptoms are observed mostly after 40 years of age, often in men. We report the unusual case of a 16-year-old girl with an elevated serum iron level and a hypoplastic kidney. Identification of heterozygosity for the HFE gene mutation C282Y/H63D confirmed the diagnosis of hemochromatosis type 1. The early detection of hemochromatosis in the presented case may delay organ damage and failure due to iron overload.     

Analysis of HFE gene mutations (C282Y, H63D, and S65C) in the Ecuadorian population

Type 1 hemochromatosis is a disorder of iron metabolism mostly related to the HFE gene mutations. In the present study, we performed a mutation analysis to determine the frequencies of the HFE gene mutations (C282Y, H63D, and S65C) in DNA samples of 100 healthy Ecuadorian individuals. We used the polymerase chain reaction (PCR) to amplify exons 2 and 4 of the HFE gene and then the restriction fragment length polymorphism (RFLP) method to detect the mutations. The results revealed that the mutations in the normal Ecuadorian population have frequencies of 0.0, 0.035, and 0.04 for C282Y, H63D, and S65C, respectively. We also searched for these mutations in 12 hemochromatosis patients, and the frequencies that we found were 0.0 for C282Y, 0.167 for H63D, and 0.042 for S65C. We found differences [using the chi-square (²) test] in the frequency of the H63D mutation between the control group and the group of hemochromatosis patients (p<0.01). This suggests that in Ecuador, type 1 hemochromatosis is more influenced by the H63D mutation than the other two mutations that we analyzed. Given that in a Caucasian population hereditary hemochromatosis is mostly related to the C282Y mutation, it is possible that the findings for the Ecuadorian population are due to geographical differences between the populations.     

Prevalence of H63D,S65C,and C282Y hereditary hemochromatosis gene variants in Madeira Island (Portugal)

Hereditary HFE Hemochromatosis is an inherited disorder of iron metabolism that results from mutations in the HFE gene. Almost all patients with hereditary hemochromatosis show a C282Y mutation in homozygosity or in compound heterozygosity with H63D. Also, the mutation S65C has been shown to be associated to a milder iron overload. Since allele and genotype frequencies of these three variants of the HFE gene vary between populations, the determination of their prevalence in Madeira Island will clarify the population susceptibility to hereditary hemochromatosis. One hundred and fifty-four samples from Madeira Island were genotyped for the three most common HFE gene mutations, H63D, C282Y, and S65C, by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Results have shown a prevalence of 20.5%, 0.33%, and 1% for H63D, C282Y, and S65C, respectively. Accordingly to our estimates, both genotypes associated to hereditary hemochromatosis, C282Y homozygotes and C282/H63D compound heterozygotes, could be present in Madeira Island population in 1,648 individuals, which represents 0.65% of the total population.     

Hereditary hemochromatosis gene (HFE) mutations C282Y, H63D and S65C in patients with idiopathic dilated cardiomyopathy

BACKGROUND: Hereditary hemochromatosis (HH), a common autosomal recessive disease, leads to excessive iron accumulation in some organs, including the heart. It is therefore not surprising that cardiomyopathy is one of the most severe complications of HH. The HFE gene defects have been thought to contribute to idiopathic dilated cardiomyopathy (IDCM) in some patients, even though the results of genotype analyses have so far been contradictory. Hence we set out here to evaluate the prevalence and potential role of HFE mutations in patients with IDCM. METHODS: A total of 91 IDCM patients and 102 controls were subjected to HFE mutation analyses, in which C282Y, H63D and S65C mutations were determined for each patient. We also analyzed the impact of the C282Y and H63D mutations on the left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF) and New York Heart Association (NYHA) functional classes. RESULTS: The prevalences of heterozygosity for the C282Y, H63D and S65C mutations in the IDCM patients were 13.2%, 22.0% and 2.2%, respectively. LVEDD was significantly higher (P=0.037) in those with the C282Y mutation at the end of the follow-up period than in those with no mutation. CONCLUSIONS: Our data showed no significant deviations in C282Y, H63D and S65C mutation frequencies between the IDCM patients and controls, suggesting that these mutations do not increase the risk of IDCM. Heterozygosity for the C282Y mutation may nevertheless be a modifying factor contributing to LV dilatation and remodeling.     

Frequency of the C282Y and H63D mutations of the hemochromatosis gene (HFE) in a cohort of 1,000 neonates in Madrid (Spain)

For centuries in Europe, population movements have contributed to ethnic groups, cultures, and consequently, inheritance mixing. There are certain genetic diseases such as hereditary hemochromatosis whose distribution is directly related to the population movements. The objective of the present investigation was to determine the C282Y and H63D mutation frequency of the HFE gene in a cohort study of 1,000 neonates in the Community of Madrid (Spain), thus contributing to the HFE gene mutations distribution research in Europe and establishing the origin of the mutations in Spain. The allelic frequency of C282Y mutation was 1.7% (CI 95% 1.1–2.3) and the H63D allele was present in 16.4% of chromosomes (CI 95% 14.8–18). In Spain, the presence of C282Y mutation and its distribution could be due more to Celtic than to Viking legacy, whereas it is assumed that the one in relation to the H63D variant occurred in the Basque Country during the Paleolithic Period.     

Effects of C282Y, H63D, and S65C HFE gene mutations, diet, and life-style factors on iron status in a general Mediterranean population from Tarragona, Spain

Mutations in the HFE gene result in iron overload and can produce hereditary hemochromatosis (HH), a disorder of iron metabolism characterized by increased intestinal iron absorption. Dietary quality, alcoholism and other life-style factors can increase the risk of iron overload, especially among genetically at risk populations. Polymorphisms of the HFE gene (C282Y, H63D and S65C) were measured together with serum ferritin (SF), transferrin saturation (TS) and hemoglobin, to measure iron status, in randomly-selected healthy subjects living in the Spanish Mediterranean coast (n = 815; 425 females, 390 males), 18 to 75 years of age. The intake of dietary components that affect iron absorption was calculated from 3-day dietary records. The presence of C282Y/H63D compound heterozygote that had a prevalence of 2.8% in males and 1.2% in females was associated with an elevated TS and SF. No subject was homozygous for C282Y or S65C. The C282Y heterozygote, H63D heterozygote and homozygote and H63D/S65C compound heterozygote genotypes were associated with increased TS relative to the wild type in the general population. These genotypes together with the alcohol and iron intake increase the indicators of iron status, while calcium intake decreases them. We did not observe any affect of the S65C heterozygote genotype on these levels. All the HFE genotypes except for the S65C heterozygote together with the alcohol, iron and calcium intake affect the indicators of iron status. The C282Y/H63D compound heterozygote genotype has the higher phenotypic expression in our Spanish Mediterranean population.     

Frequency of the HFE C282Y and H63D mutations in Danish patients with clinical haemochromatosis initially diagnosed by phenotypic methods

AIM: To assess the frequency of the C282Y and H63D mutations on the HFE gene in Danish patients with clinical hereditary haemochromatosis initially diagnosed by phenotypic methods. METHODS: In the period 1950-1985, an epidemiological survey in Denmark identified 179 patients with clinical idiopathic haemochromatosis diagnosed by phenotypic methods (serum transferrin saturation, serum ferritin, liver biopsy and mobilisable body iron stores). In 32 unrelated patients, frozen blood samples were available for genetic analysis. In a subsequent series of 26 unrelated Danish patients, a phenotypic diagnosis of clinical idiopathic haemochromatosis was made before blood samples were taken for HFE genotyping. The total series consisted of 58 patients (40 men and 18 women) with a median age of 60 yrs (range 18-74). HFE genotyping was performed by the polymerase chain reaction (PCR) technique. RESULTS: Among the patients, 55 of 58 (94.8%) were C282Y/C282Y homozygous. One 63-year-old woman (1.7%) was compound C282Y/H63D heterozygous. Two women (3.4%), aged 42 and 43 yrs were negative for both the C282Y and the H63D mutation. CONCLUSION: In the Danish population, homozygosity for the C282Y mutation appears to be the prevailing cause of clinically overt genetic haemochromatosis. This finding has implications both for the evaluation of patients with iron overload disorders and for the strategy in future population screening surveys.     

Frequency of primary iron overload and HFE gene mutations （C282Y, H63D and S65C） in chronic liver disease patients in north India

AIM:To identify the frequency of iron overload and study the three mutations in the HFE gene (C282Y,H63D,and S65C) in patients with chronic liver disorders (CLD) and controls. METHODS:To identify patients with iron overload (transferrin saturation > 45% in females and > 50% in males and serum ferritin > 1000 ng/mL) we evaluated 236 patients with CLD,including 59 with non-alcoholic steatohepatitis (NASH),22 with alcoholic liver disease (ALD),19 of cirrhosis due to viruses (HBV,HCV),and 136 with cryptogenic cirrhosis. Mutations of the HFE gene were analyzed by PCR-RE. hundred controls were screened for iron status and the mutations. RESULTS:Seventeen patients with CLD showed evidence of iron overload. Fifteen cases of iron overload had cryptogenic cirrhosis and two had ALD. None of the controls showed iron overload. We did not find any individual with 282Y or 65C either in the cases or in the controls. The prevalence of H63D heterozygosity was 12% in normal individuals,14.8% in 236 patients (16.9% in NASH,13.6% in ALD,26.3% in viral and 12.5% in cryptogenic cirrhosis) and the overall prevalence was 13.98%. Only two of the 17 patients with primary iron overload were heterozygous for H63D. One patient with NASH and one normal individual who were homozygous for H63D showed no iron overload.CONCLUSION:Primary iron overload in Indians is nonHFE type,which is different from that in Europeans and further molecular studies are required to determine the defect in various iron regulatory genes.     

Prevalence of HFE genotypes, C282Y and H63D, in patients with hematologic disorders

BACKGROUND AND OBJECTIVES: Iron status has implications for normal erythrocyte and leukocyte function and for platelet count, size and activation. Increased storage of iron is considered a potential risk factor participating in the pathogenesis of malignant diseases. Since HFE gene mutations have recently been implicated in unbalanced iron homeostasis, we set out to examine the prevalence of these mutations in patients with hematologic disorders. DESIGN AND METHODS: C282Y and H63D mutations were determined in 232 patients with various hematologic disorders treated at Oulu University Hospital between 1987 and 2000. DNA samples extracted from either the peripheral blood or bone marrow of these patients were amplified by a polymerase chain reaction (PCR) method using sequence-specific primers, and the products were analyzed on agarose gels. RESULTS: There was a slight tendency towards lower frequencies of the C282Y allele in patients with acute myeloid leukemia (AML) (3.8%, n=53) and higher frequencies in those with essential thrombocythemia (ET) (16.2%, n=37). Contrary to some expectations, however, the frequency of the C282Y allele in acute lymphoblastic leukemia turned out to be normal (7.0%, n=43). Our data showed no significant deviations in H63D mutation frequency in any of the categories of patients. INTERPRETATION AND CONCLUSIONS: Our results do not show any significant association between HFE gene mutations and hematologic malignancies. The divergent frequencies observed for the C282Y mutation in patients with AML and ET highlight the need for larger population studies of HFE mutations in patients with hematologic diseases.     

C282Y and H63D mutations of the haemochromatosis gene in patients with iron overload.

OBJECTIVE: To determine the relevance of C282Y and H63D mutations of HEF gene in patients with iron overload. PATIENTS AND METHODS: Patients with iron overload referred to our Liver Unit were included in the study. The association of mutations to different diagnosis and their impact on the severity of the hepatopathy were explored. Sensitivity, specificity and positive and negative predictive values of mutations for the diagnosis of haemochromatosis were determined. RESULTS: The study included 78 patients with iron overload. The control group included 21 patients of similar age and sex ratio without iron overload nor hepatopathy. Twenty three patients had haemochromatosis, 22 alcoholic liver disease and 33 other diseases unrelated to iron metabolism. Seventy three per cent of patients with haemochromatosis were homozygous for the C282Y mutation. All the C282Y homozygous subjects had also haemochromatosis. Fifty three per cent of patients with alcoholic hepatopathy had some kind of mutation. This has been also observed in 70% of patients with iron-unrelated diseases. Such percentage was significantly greater than in the control group (24% with H63D mutation). C282Y homozygosity in patients with iron overload had a sensitivity of 73.9%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value of 89.6%. CONCLUSIONS: In our population, as in all the Western countries, haemochromatosis is mainly associated to homozygous C282Y mutation. The high frequency of mutations in patients with iron overload and without haemochromatosis suggests the involvement of such mutations in iron overload.     

Prevalence of C282Y,H63D,and S65C mutations in hereditary <Emphasis Type="Italic">HFE</Emphasis>-hemochromatosis gene in Lithuanian population

HFE-hemochromatosis is a common autosomal recessive disease caused by HFE gene mutations and characterized as iron overload and failure of different organs. The aim of this study was to determine the prevalence of C282Y (c.845 G > A), H63D (c.187 C > G), and S65C (c.193A > T) alleles of HFE gene in the Lithuanian population. One thousand and eleven healthy blood donors of Lithuanian nationality were examined in four different ethnic Lithuanian regions to determine HFE gene alleles and genotype frequencies. The samples of DNA were analyzed for the presence of restriction fragment length polymorphism and validated by DNA sequencing. Among 1,011 blood donors tested, the frequency of C282Y, H63D, and S65C alleles were 2.6%, 15.9%, and 1.9%, respectively. One third of the tested subjects (n = 336) had at least one of the C282Y or H63D HFE gene mutations. The screening of Lithuanian blood donors has detected 13 (1.3%) subjects with a genotype C282Y/C282Y or C282Y/H63D responsible for the development of HFE-hemochromatosis. The prevalence of C282Y mutation was significantly higher among the inhabitants of Zemaitija (Somogitia) at the Baltic Sea area (5.9%) in comparison to the regions of continental part of Lithuania (2.4% in Dzukija, 2.3% in Aukstaitija, and 2% in Suvalkija, p < 0.05). These data support the hypothesis that the p.C282Y mutation originated from Scandinavia and spread with the Vikings along the Baltic Sea coast. The first epidemiological investigation of HFE gene mutations in ethnic Lithuanians showed that the frequencies of H63D, C282Y, and S65C of HFE gene alleles are similar to the other North-Eastern Europeans, especially in the Baltic region (Estonia, Latvia), Poland, and part of Russia (Moscow region).     

The clinical relevance of compound heterozygosity for the C282Y and H63D substitutions in hemochromatosis.

BACKGROUND & AIMS: Two major mutations are defined within the hemochromatosis gene, HFE. Although the effects of the C282Y substitution have been well characterized, the clinical significance of the C282Y/H63D state remains unclear. This study assessed the phenotypic expression in C282Y/H63D subjects as compared with C282Y homozygotes. METHODS: Data were obtained from 91 C282Y/H63D probands, 158 C282Y/H63D subjects identified through family screening, and 483 C282Y homozygotes. Subjects underwent clinical evaluation, genotyping, biochemical assessment, and liver biopsy examination where clinically indicated. RESULTS: C282Y/H63D probands had significantly less clinical and biochemical expression than C282Y homozygotes. Biochemical expression was higher in C282Y/H63D probands than in C282Y/H63D subjects identified through family screening (P < .001). Of the C282Y/H63D subjects with serum ferritin levels greater than 1000 mug/L, all had known comorbid factors that could have contributed to the increased ferritin level. Of the 51 C282Y/H63D subjects who underwent liver biopsy examination, significantly increased iron stores were present in 9 subjects and hepatic fibrosis was present in 13. Twelve of the 13 had evidence of hepatic steatosis, excess alcohol consumption, or diabetes. The mobilizable iron level was significantly higher in C282Y homozygous males than in compound heterozygous males (P < .001). Genetic screening of C282Y/H63D first-degree relatives detected 5 C282Y homozygotes. CONCLUSIONS: C282Y/H63D subjects referred for assessment had a high prevalence of increased iron indices but did not develop progressive clinical disease without comorbid factors such as steatosis, diabetes, or excess alcohol consumption. When fibrosis was seen, 1 or more comorbid factors almost always were present. Thus, phlebotomy therapy is warranted and cascade screening of relatives should be performed because expressing C282Y homozygotes may be detected.     

Distribution of the C282Y and H63D polymorphisms in hereditary hemochromatosis patients from the French Basque Country

The distribution of HFE mutations was studied in patients from the French Basque Country with hereditary hemochromatosis (HH). The C282Y mutation was underrepresented but H63D seemed to demonstrate the highest prevalence when compared with other European countries. In addition, symptomatic HH was rarer in autochthonous Basques. This profile is interesting to consider in view of population genetics and should be associated with the search for non-HFE mutations.This work was presented in part at the Eighth Congress of the European Hematology Association, Lyon, France, 12–15 June 2003.