HFE gene mutations in Brazilian thalassemic patients

Association of frequency of hereditary hemochromatosis (HFE) gene mutations (H63D and C282Y) with iron overload in beta-thalassemia major patients in Pakistan

Objectives:

To evaluate any association between the frequency of hereditary hemochromatosis (HFE) gene mutation (H63D and C282Y) and iron overload in beta-thalassemia major (BTM) patients.

Methods:

The case-control study was conducted from June 2016 to February 2018. Blood samples from 204 BTM patients and 204 normal controls were taken from the Sundas Foundation Blood Bank.

These samples were analyzed for serum ferritin assay and HFE mutation. Ferritin level was measured on the ARCHITECT 1000SR. Both patient and control samples were analyzed for mutations using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results:

Serum ferritin levels for all patients were >1000ng/mL. The p.H63D mutation was observed in 23 (11.3%) cases, out of which 19 cases were heterozygous for p.H63D and 4 cases were homozygous. In control samples, 4 cases (2%) were found heterozygous for the p.H63D, and no homozygous mutation was found. Significantly high serum ferritin levels were found in BTM patients with the H63D mutation (p=0.00). In the case of p.C282Y, neither homozygous nor heterozygous mutation was found in patients or in controls.

Conclusion:

H63D polymorphism is associated with iron overload in BTM patients. Larger-scale research is required to give an elaborated view of the association of the HFE mutation with iron overload in these patients and to confirm our conclusion.

The Correlation of Cardiac and Hepatic Hemosiderosis as Measured by T2*MRI Technique with Ferritin Levels and Hemochromatosis Gene Mutations in Iranian Patients with Beta Thalassemia Major

Objectives

Organ-specific hemosiderosis and iron overload complications are more serious and more frequent in some patients with beta thalassemia major (BTM) compared with others. We investigated whether coinheritance of HFE H63D or C282Y gene mutations in patients with BTM contributes to the phenotypic variation of iron overload complications and assessed the correlation of cardiac and hepatic hemosiderosis with plasma ferritin levels.

Methods

We studied 60 patients with BTM with a mean age of 17.5±9.1 years from the Northwest of Iran. HFE gene mutations were analyzed using the polymerase chain reaction-restriction fragment length polymorphism method. Cardiac and hepatic hemosiderosis was assessed using T2*magnetic resonance imaging (MRI). Ferritin levels were measured using the enzyme immunoassay method.

Results

Ferritin levels showed a strong inverse correlation with hepatic T2*MRI values (r = -0.631, p = 0.001) but a poor correlation with cardiac T2*MRI values (r = -0.297, p = 0.044). The correlation between cardiac T2*MRI values and hepatic T2*MRI values was poor and insignificant (r = 0.287, p = 0.058). Genotype and allele distribution of HFE H63D and C282Y mutation did not differ significantly between patients with and without hepatic or cardiac hemosiderosis (p > 0.050). However, carriers of HFE 63D allele had significantly higher ferritin levels compared with non-carriers (1 903±993 vs. 992±683, p < 0.001).

Conclusions

Cardiac T2*MRI values showed a poor correlation with hepatic T2*MRI values and ferritin levels. Accurate assessment of cardiac iron overload in patients with BTM can only be done using the T2*MRI technique. Additionally, HFE H63D is a significant determinant factor for elevated ferritin levels in BTM patients.

Inherited haemochromatosis with C282Y mutation in a patient with alpha-thalassaemia: a treatment dilemma

A Caucasian 24-year-old female patient suffers from two hereditary disorders: alpha-thalassaemia, which is prevalent in Asia and rare in Europe, and haemochromatosis, which is prevalent among northern Europe and rare in Asia. The clinical presentation and management of one of these diseases is controversial for the other. She presented 5 years ago with a clinical picture of refractory iron-deficiency anaemia secondary to menorrhagia. On treating her with the standard iron therapy, her anaemia persists although with adquate iron stores. This prompted further investigations that revealed in addition to hereditary haemochromatosis, alpha-thalassaemia because of abnormal blood indices. The treatment of thalassaemia with either iron or blood transfusion is not advisable in haemochromatosis, while standard treatment of haemochromatosis with venesection will worsen the anaemia. As iron chelating agents were not approved in Australia for haemochromatosis, haematinics support was commenced with a satisfactory improvement of anaemia thus allowing for further venesection.

Frequency of Hereditary Hemochromatosis (HFE) Gene Mutations in Egyptian Beta Thalassemia Patients and its Relation to Iron Overload

AIM:

This study aimed to detect the most common HFE gene mutations (C282Y, H63D, and S56C) in Egyptian beta thalassemia major patients and its relation to their iron status.

SUBJECTS AND METHODS:

The study included 50 beta thalassemia major patients and 30 age and sex matched healthy persons as a control group. Serum ferritin, serum iron and TIBC level were measured. Detection of the three HFE gene mutations (C282Y, H63D and S65C) was done by PCR-RFLP analysis. Confirmation of positive cases for the mutations was done by sequencing.

RESULTS:

Neither homozygote nor carrier status for the C282Y or S65C alleles was found. The H63D heterozygous state was detected in 5/50 (10%) thalassemic patients and in 1/30 (3.3%) controls with no statistically significant difference between patients and control groups (p = 0.22). Significantly higher levels of the serum ferritin and serum iron in patients with this mutation (p = 001).

CONCLUSION:

Our results suggest that there is an association between H63D mutation and the severity of iron overload in thalassemic patients.

Effects of Iron Overload on the Activity of Na,K-ATPase and Lipid Profile of the Human Erythrocyte Membrane

Iron is an essential chemical element for human life. However, in some pathological conditions, such as hereditary hemochromatosis type 1 (HH1), iron overload induces the production of reactive oxygen species that may lead to lipid peroxidation and a change in the plasma-membrane lipid profile. In this study, we investigated whether iron overload interferes with the Na,K-ATPase activity of the plasma membrane by studying erythrocytes that were obtained from the whole blood of patients suffering from iron overload. Additionally, we treated erythrocytes of normal subjects with 0.8 mM H₂O₂ and 1 μM FeCl₃ for 24 h. We then analyzed the lipid profile, lipid peroxidation and Na,K-ATPase activity of plasma membranes derived from these cells. Iron overload was more frequent in men (87.5%) than in women and was associated with an increase (446%) in lipid peroxidation, as indicated by the amount of the thiobarbituric acid reactive substances (TBARS) and an increase (327%) in the Na,K-ATPase activity in the plasma membrane of erythrocytes. Erythrocytes treated with 1 μM FeCl₃ for 24 h showed an increase (132%) in the Na,K-ATPase activity but no change in the TBARS levels. Iron treatment also decreased the cholesterol and phospholipid content of the erythrocyte membranes and similar decreases were observed in iron overload patients. In contrast, erythrocytes treated with 0.8 mM H₂O₂ for 24 h showed no change in the measured parameters. These results indicate that erythrocytes from patients with iron overload exhibit higher Na,K-ATPase activity compared with normal subjects and that this effect is specifically associated with altered iron levels.

Analysis of HFE genes C282Y, H63D, and S65D in patients with hyperferritinemia from northeastern Brazil

BACKGROUND

Hereditary hemochromatosis (HH) is a genetic disease caused by the high absorption and deposition of iron in several organs. This accumulation results in several clinical complications such as cirrhosis, arthritis, cardiopathies, diabetes, sexual disorders, and skin darkening. The H63D and C282Y mutations are well defined in the HH etiology. The objective of this article is identification of the H63D and C282Y mutations in the HFE protein gene and the frequency assessment of these mutations in patients with persistent increase of serum ferritin in patients from Natal City from state of Rio Grande do Norte, located in northeastern Brazil.

RESULTS

Of the 299 patients studied for C282Y and H63D, 48.49% showed absence of mutation and 51.51% showed some sort of mutation: heterozygous C282Y mutation in 4.35% patients, homozygous C282Y mutation in 2.67% patients, heterozygous H63D mutation in 31.44% patients, homozygous H63D mutation in 8.03% patients, and heterozygous for the mutation in both genes (C282Y/H63D) in 5.02% patients. The S65C mutation was studied in 112 patients and heterozygous mutation (S65D/WT) in 2.67% of patients and double mutation (H63D/S65C) in 1.78% of patients were observed.

CONCLUSION

Due to the high prevalence of hemochromatosis, its genetic diagnosis has become a challenge, especially in the high-risk group.