Effect of Hereditary Hemochromatosis Gene H63D and C282Y Mutations on Iron Overload in Sickle Cell Disease Patients.

OBJECTIVE: Hemochromatosis is an autosomal recessive disease that is one of the most important reasons for iron overload. Sickle cell disease is a hemoglobinopathy that occurs as a result of a homozygous mutation in the hemoglobin gene. Erythrocyte transfusion is frequently used in the treatment of this disease. Iron overload as a result of transfusion is important in the mortality and morbidity of sickle cell anemia patients as well as in other hemoglobinopathies. In this study, the effect of hemochromatosis gene (HFE) p.H63D and p.C282Y mutations on transfusion-related cardiac and liver iron overload in sickle cell disease patients who carry homozygous hemoglobin S mutation has been investigated. MATERIALS AND METHODS: This is a prospective single-center cross-sectional study in patients with homozygous hemoglobin S mutation between the years 2008 and 2013. The patients were divided into two groups. The first group (group A, n=31) was receiving chelation therapy and the second group (group B, n=13) was not. Direct and indirect iron loads were analyzed by magnetic resonance imaging and biochemically, respectively. HFE gene mutations were analyzed by polymerase chain reaction-restriction fragment length polymorphism method. Statistical analyses were performed by independent samples t-test. RESULTS: p.H63D mutation was detected in 10 (32.3%) patients in group A and in only 1 patient (7.7%) in group B. When the 2 groups were compared for iron overload, iron deposition in the liver was significantly higher in group B (p=0.046). In addition, in group A, iron deposition was significantly higher in HFE mutation carriers compared to patients without the mutation (p=0.05). CONCLUSION: Results of this study showed that HFE gene mutations are important in iron deposition in the liver in patients with sickle cell disease.

Fluorescence in situ hybridization analysis of the hTERC region in acute myeloid leukemia patients.

OBJECTIVE: The telomerase RNA component (hTERC) gene is located at 3q26. Increased hTERC gene expression has been frequently observed and amplification was shown using fluorescence in situ hybridization (FISH) in different cancers. The aim of this study was to determine whether hTERC gene amplification is detectable by FISH in acute myeloid leukemia (AML) cells. METHODS: FISH and karyotype results at the time of diagnosis of 23 adult AML patients were retrospectively evaluated. Additionally, fixed cells were hybridized with an hTERC region-specific FISH probe to determine gene amplification. RESULTS: Ten of the 23 patients had a normal karyotype and 6 had an abnormal karyotype. hTERC region amplification was not observed in any of the patients. CONCLUSION: Although it was reported that hTERC gene amplification may partially contribute to increased telomerase expression and activity in leukemic cells, it is not possible to make such a conclusion based on the results of the this study, as hTERC amplification was not observed in the study group. This suggests that increased telomerase activity via gene amplification in the development of AML may not be as important a factor as it is in solid tumors.

Complex cytogenetic findings in the bone marrow of a chronic idiopathic myelofibrosis patient.

Chronic idiopathic myelofibrosis is a myeloproliferative disorder characterized by splenomegaly, myeloid metaplasia and reactive bone marrow fibrosis. Karyotype analysis of the bone marrow is an integral part of the diagnosis, especially as a discriminative tool in ruling out reactive conditions. The frequency of clonal cytogenetic anomalies in this disease is the highest among its group, varying between 30 and 75%. Among these, trisomy 1q, 20q-, 13q- and +8 are the most common aberrations. Here we report a 66-year-old male patient whose bone marrow biopsy revealed signs of chronic myeloproliferative changes and dysmegakaryopoiesis. He was administered hydroxyurea treatment, splenic radiotherapy and multiple transfusions. The patient worsened in the following months and the second bone marrow biopsy revealed myelofibrosis. Cytogenetic analysis of this bone marrow sample revealed a complex karyotype reported to be 46,XY,del(9)(q22q34),t(8;17;21)(q22;q21;q22)[23]/46,XY[2], with a previously undefined three-way translocation and deletion in chromosome 9. The patient died shortly thereafter.