1
|
Lee YC, Yen CT, Lee YL, Chen RJ. Thalassemia Intermedia: Chelator or Not? Int J Mol Sci 2022; 23:ijms231710189. [PMID: 36077584 PMCID: PMC9456380 DOI: 10.3390/ijms231710189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/19/2022] Open
Abstract
Thalassemia is the most common genetic disorder worldwide. Thalassemia intermedia (TI) is non-transfusion-dependent thalassemia (NTDT), which includes β-TI hemoglobin, E/β-thalassemia and hemoglobin H (HbH) disease. Due to the availability of iron chelation therapy, the life expectancy of thalassemia major (TM) patients is now close to that of TI patients. Iron overload is noted in TI due to the increasing iron absorption from the intestine. Questions are raised regarding the relationship between iron chelation therapy and decreased patient morbidity/mortality, as well as the starting threshold for chelation therapy. Searching all the available articles up to 12 August 2022, iron-chelation-related TI was reviewed. In addition to splenectomized patients, osteoporosis was the most common morbidity among TI cases. Most study designs related to ferritin level and morbidities were cross-sectional and most were from the same Italian study groups. Intervention studies of iron chelation therapy included a subgroup of TI that required regular transfusion. Liver iron concentration (LIC) ≥ 5 mg/g/dw measured by MRI and ferritin level > 300 ng/mL were suggested as indicators to start iron chelation therapy, and iron chelation therapy was suggested to be stopped at a ferritin level ≤ 300 ng/mL. No studies showed improved overall survival rates by iron chelation therapy. TI morbidities and mortalities cannot be explained by iron overload alone. Hypoxemia and hemolysis may play a role. Head-to-head studies comparing different treatment methods, including hydroxyurea, fetal hemoglobin-inducing agents, hypertransfusion as well as iron chelation therapy are needed for TI, hopefully separating β-TI and HbH disease. In addition, the target hemoglobin level should be determined for β-TI and HbH disease.
Collapse
Affiliation(s)
- Yen-Chien Lee
- Department of Medical Oncology, Tainan Hospital, Ministry of Health and Welfare, Executive Yuan, Tainan 70043, Taiwan
- Department of Internal Medicine, College of Medicine, National Cheng Kung University Hospital, Tainan 70403, Taiwan
- Correspondence: (Y.-C.L.); (R.-J.C.)
| | - Chi-Tai Yen
- Department of Internal Medicine, Tainan Hospital, Ministry of Health and Welfare, Executive Yuan, Tainan 70043, Taiwan
| | - Yen-Ling Lee
- Department of Medical Oncology, Tainan Hospital, Ministry of Health and Welfare, Executive Yuan, Tainan 70043, Taiwan
| | - Rong-Jane Chen
- Department of Food Safety/Hygiene and Risk Management, College of Medicine, National Cheng Kung University, Tainan 70403, Taiwan
- Correspondence: (Y.-C.L.); (R.-J.C.)
| |
Collapse
|
2
|
Ropero P, González Fernández FA, Nieto JM, Torres-Jiménez WM, Benavente C. β-Thalassemia Intermedia: Interaction of α-Globin Gene Triplication With β-thalassemia Heterozygous in Spain. Front Med (Lausanne) 2022; 9:866396. [PMID: 35402459 PMCID: PMC8985499 DOI: 10.3389/fmed.2022.866396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Accepted: 02/28/2022] [Indexed: 11/17/2022] Open
Abstract
Objectives To verify with hematimetric data that the diagnosis and clinical grade of β-TI can be established when a triplication of alpha genes (αααanti 3.7) and heterozygous β-thalassemia coexist. Materials and Methods Retrospective study in which 73 patients of Caucasian origin participated, who simultaneously showed a triplication or quadruplication of genes α and β-thalassemia. Screening for the most frequent α-thalassemia mutations as well as gene triplication (αααanti 3.7) was carried out by multiplex PCR followed by reverse hybridization with a commercial Alpha-Globin StripAssay kit and confirmed by MLPA (Multiplex ligation-dependent probe amplification). The molecular diagnosis of β-thalassemia was carried out by automatic sequencing according to the Sanger method. Results The genotypes have been classified into three groups according to the number of α globin genes and the severity of the alteration in the β globin gene. All had a mutation in the HBB gene (β0-thalassemia, β+-thalassemia severe, and β+-thalassemia mild). Group I patients who have coherent 6 α genes and groups II and III with 5 α globin genes. In group III, the patients were carriers of mutations affecting the β and δ globin genes. The most significant hematological parameters were hemoglobin levels, MCV, RDW, and the percentage of Hb F. Conclusions In group I, regardless of the distribution of the 6 α globin genes, homozygous triplication (ααα/ααα) or heterozygous quadruplication (αααα/αα), the association with heterozygous β-thalassemia results in severe to moderate anemia that may or may not require transfusion therapy, is the severity of the HBB gene mutation that would determine the clinical variation. Group II patients phenotypically behaved like mild thalassemia intermedia, except for one case that presented thalassemic trait because it also presented an associated α-thalassemia (ααα/-α3.7). Finally, group III patients behaved as a thalassemic trait since all were carriers of mutations that increase the overexpression of γ genes.
Collapse
Affiliation(s)
- Paloma Ropero
- Hematology Service, Hospital Clínico San Carlos, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital Clínico San Carlos, Madrid, Spain
- *Correspondence: Paloma Ropero
| | | | - Jorge M. Nieto
- Hematology Service, Hospital Clínico San Carlos, Madrid, Spain
- Instituto de Investigación Sanitaria Hospital Clínico San Carlos, Madrid, Spain
| | | | | |
Collapse
|
3
|
Amin SS, Jalal SD, Ali KM, Mohammed AI, Rasool LK, Osman TJ. Beta-Thalassemia Intermedia: A Single Thalassemia Center Experience from Northeastern Iraq. BIOMED RESEARCH INTERNATIONAL 2020; 2020:2807120. [PMID: 32190657 PMCID: PMC7066418 DOI: 10.1155/2020/2807120] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2019] [Accepted: 02/13/2020] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To determine the molecular characterization and disease-associated complications of beta-thalassemia intermedia (β-TI) patients in Sulaymaniyah province, northeastern Iraq. METHODS A total of 159 β-TI) patients in Sulaymaniyah province, northeastern Iraq. β-TI) patients in Sulaymaniyah province, northeastern Iraq. RESULTS Nineteen different β-globin gene mutations arranged in 37 various genotypes were determined. The most frequent were IVS-II-I (G>A) (47.2%), followed by IVS-I-6 (T>C) (23.3%) and IVS-I-110 (G>A) (5%). Among disease-related morbidities documented, bone disease amounted to 53% (facial deformity and osteoporosis), followed by endocrinopathies 17.6% (growth retardation and subclinical hypothyroidism), cholelithiasis 13.8%, pulmonary hypertension 11.3%, and abnormal liver function test 7.5%, whereas venous thrombosis, extramedullary hemopoiesis, and leg ulcer were less frequently observed. Age ≥ 35 and female sex were risk factors for cholelithiasis, while age was an independent risk for hypothyroidism and female sex was associated with increased risk for osteoporosis. Mean serum ferritin of ≥1000 μg/L was associated with an increased risk of osteoporosis, whereas chelation therapy was protective for a multitude of other complications. Transfusion, on the other hand, increased the risk of osteoporosis, yet it was protective for cholelithiasis and hypothyroidism. Moreover, splenectomy was protective for cholelithiasis, although it was an independent risk for hypothyroidism. Finally, hydroxyurea was associated with an increased risk of osteoporosis, while it was protective for cholelithiasis. Discussion and Conclusion. β +-thalassemia mutation had contributed to 41.25 of families with a less severe β-thalassemia phenotype in the northeastern part of Iraq, justifying the need to investigate the contribution of genetic modifiers in ameliorating disease severity. In addition, the substantial number of β-TI patients developed disease-related morbidities, which necessitates the need for more appropriate clinical management with earlier intervention.β-TI) patients in Sulaymaniyah province, northeastern Iraq. μg/L was associated with an increased risk of osteoporosis, whereas chelation therapy was protective for a multitude of other complications. Transfusion, on the other hand, increased the risk of osteoporosis, yet it was protective for cholelithiasis and hypothyroidism. Moreover, splenectomy was protective for cholelithiasis, although it was an independent risk for hypothyroidism. Finally, hydroxyurea was associated with an increased risk of osteoporosis, while it was protective for cholelithiasis. Discussion and Conclusion. β +-thalassemia mutation had contributed to 41.25 of families with a less severe β-thalassemia phenotype in the northeastern part of Iraq, justifying the need to investigate the contribution of genetic modifiers in ameliorating disease severity. In addition, the substantial number of β-TI patients developed disease-related morbidities, which necessitates the need for more appropriate clinical management with earlier intervention.Discussion and Conclusion. β +-thalassemia mutation had contributed to 41.25 of families with a less severe β-thalassemia phenotype in the northeastern part of Iraq, justifying the need to investigate the contribution of genetic modifiers in ameliorating disease severity. In addition, the substantial number of β-TI patients developed disease-related morbidities, which necessitates the need for more appropriate clinical management with earlier intervention.β-TI) patients in Sulaymaniyah province, northeastern Iraq. β-TI) patients in Sulaymaniyah province, northeastern Iraq.
Collapse
Affiliation(s)
- Shaema Salih Amin
- Sulaymaniyah Directorate of Health, Hewa Oncology Hospital, Sulaymaniyah, Iraq
| | - Sana Dlawar Jalal
- Department of Pathology, College of Medicine, University of Sulaymaniyah, Sulaymaniyah, Iraq
| | - Kosar Muhammed Ali
- Department of Medicine, College of Medicine, University of Sulaymaniyah, Sulaymaniyah, Iraq
| | - Ali Ibrahim Mohammed
- Department of Pathology, College of Medicine, University of Sulaymaniyah, Sulaymaniyah, Iraq
| | | | - Tara Jamel Osman
- Thalassemia and Congenital Blood Disorders Center, Sulaymaniyah 46001, Iraq
| |
Collapse
|
4
|
Xie J, Zhou Y, Xiao Q, Long R, Li L, Li L. Rare double heterozygosity for poly A(A〉 G) and CD17(A〉 T) of beta thalassemia intermedia in a Chinese family. Hematol Rep 2019; 11:7911. [PMID: 31579136 PMCID: PMC6761475 DOI: 10.4081/hr.2019.7911] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 07/05/2019] [Indexed: 11/23/2022] Open
Abstract
Beta thalassemia is a hereditary disorder resulted from mutations in the β globin gene leading to alpha/beta imbalance, ineffective erythropoiesis, and chronic anemia. Three types have been defined, based on the degree of reduced beta-globin chain synthesis and clinical phenotype: major, intermedia and minor (heterozygote carrier state). Beta thalassemia intermedia is characterized by heterogeneity for the wide clinical spectrum of various genotypes and a wide range of presentations. The genotypes of beta thalassemia intermedia are much complicated referring to β+/β+,β+/β0, Hb E/β0, β0/β0 compounding alpha thalassemia and so on. In this present case, we reported a rare beta thalassemia intermedia genotype of double heterozygosity for poly A (A〉 G) and CD17(A〉 T) indicated of β+/β0 in a Chinese family.
Collapse
Affiliation(s)
- Jianhong Xie
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai, China
| | - Yuqiu Zhou
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai, China
| | - Qizhi Xiao
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai, China
| | - Ruoting Long
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai, China
| | - Lianxiang Li
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai, China
| | - Lei Li
- Department of Clinical Laboratory, Zhuhai Municipal Maternal and Child Healthcare Hospital, Zhuhai, China
| |
Collapse
|
5
|
Perera S, Allen A, Silva I, Hapugoda M, Wickramarathne MN, Wijesiriwardena I, Allen S, Rees D, Efremov DG, Fisher CA, Weatherall DJ, Premawardhena A. Genotype-phenotype association analysis identifies the role of α globin genes in modulating disease severity of β thalassaemia intermedia in Sri Lanka. Sci Rep 2019; 9:10116. [PMID: 31300739 PMCID: PMC6625979 DOI: 10.1038/s41598-019-46674-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2018] [Accepted: 06/28/2019] [Indexed: 01/14/2023] Open
Abstract
β thalassaemia intermedia (βTI) are a heterogeneous group of disorders known to be extremely phenotypically diverse. This group is more complex to manage as no definitive treatment guidelines exist unlike for β thalassaemia major (βTM). There are only a few studies looking at genotype phenotype associations of βTI outside the Mediterranean region. The reasons for the diverse clinical phenotype in βTI are unknown. We categorized fifty Sri Lankan patients diagnosed with βTI as mild, moderate or severe according to published criteria. DNA samples were genotyped for β thalassaemia mutations, α globin genotype and copy number and known genetic modifiers of haemoglobin F production. There were 26/50 (52.0%) in mild group and 12/50 (24.0%) each in moderate and sever categories. 18/26 (69.2%) classified as mild were β heterozygotes and 17/18 (94.4%) had excess α globin genes. 11/12 (91.6%) classified as moderate were β heterozygotes and 8/11 (72.2%) had excess α globin genes. In contrast, 8/12 (66.7%) classified as severe were β homozygotes and 7/8(87.5%) had α globin gene deletions. In Sri Lanka, co-inheritance of either excess α globin genes in β thalassaemia heterozygotes or α globin gene deletions in β thalassaemia homozygotes is a significant factor in modulating disease severity.
Collapse
Affiliation(s)
- Shiromi Perera
- Faculty of Medicine, University of Kelaniya, Kelaniya, Sri Lanka.
| | - Angela Allen
- MRC Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
- Centre for Tropical and Infectious Disease, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Ishari Silva
- Hemal's Thalassemia Care Unit, North Colombo Teaching Hospital, Ragama, Sri Lanka
| | - Menaka Hapugoda
- Faculty of Medicine, University of Kelaniya, Kelaniya, Sri Lanka
| | | | | | - Stephen Allen
- Centre for Tropical and Infectious Disease, Liverpool School of Tropical Medicine, Liverpool, UK
| | - David Rees
- Department of Paediatric Haematology, King's College Hospital, London, UK
| | - Dimitar G Efremov
- Molecular Hematology Unit, International Centre for Genetic Engineering and Biotechnology, Rome, Italy
| | - Christopher A Fisher
- MRC Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - David J Weatherall
- MRC Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Anuja Premawardhena
- Faculty of Medicine, University of Kelaniya, Kelaniya, Sri Lanka
- Hemal's Thalassemia Care Unit, North Colombo Teaching Hospital, Ragama, Sri Lanka
| |
Collapse
|
6
|
Faraon R, Daraghmah M, Samarah F, Srour MA. Molecular characterization of β-thalassemia intermedia in the West Bank, Palestine. BMC HEMATOLOGY 2019; 19:4. [PMID: 30820323 PMCID: PMC6380065 DOI: 10.1186/s12878-019-0135-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/02/2018] [Accepted: 02/07/2019] [Indexed: 12/23/2022]
Abstract
BACKGROUND We aimed to investigate the molecular basis of β-Thalassemia intermedia (TI) in the West Bank region and its management practices. METHODS This was a case series multi-center study and included 51 cases of TI. DNA sequencing was used to analyze β-globin gene mutations. Common α-globin gene mutations were screened by Gap-PCR (-α3.7, -α4.2, --MED, αααanti3.7) or DNA sequencing (α2-IVS II 5 nt del). XmnI -158 C > T polymorphisms of Gγ-globin gene was determined by RFLP-PCR. RESULTS Seven β-globin gene mutations were observed, namely IVS-I -6 C > T, IVS-I-110 G > A, IVS-II-1 G > A, IVS-I-1 G > A, Codon 37 Trp > Stop, beta - 101 and IVS-II-848 C > A. Ten genotypes were observed. Homozygosity for IVS-I-6 accounted for the majority of TI cases with a frequency of 74.5%. The second common β-globin gene genotype was homozygote IVS-I-110 G > A (5.8%) and homozygote IVS-II-1 G > A (5.8%). The remaining seven genotypes were each detected in about 2% of patients. α-Thalassemia mutations were seen in five patients (9.8%), and included (-α3.7, αααanti3.7 and α2-IVSII-5 nt del). XmnI polymorphism was observed in four patients (7.8%), three homozygotes and one heterozygote. CONCLUSIONS Homozygosity for the mild β-globin gene IVS-I-6 allele was the major contributing factor for the TI phenotype among the study subjects. The role of XmnI SNP and α-thalassemia mutations in ameliorating the TI phenotype was observed in few patients for each factor. The beta - 101 C > T mutation was diagnosed in one patient in homozygote state for the first time in Palestine.
Collapse
Affiliation(s)
- Rashail Faraon
- Department of Medical Laboratory Sciences, Al-Quds University, East Jerusalem, Palestine
| | - Mahmoud Daraghmah
- Palestine Thalassemia Patients’ Friends Society, Al-Bireh, Palestine
| | - Fekri Samarah
- Department of Medical Laboratory Sciences, Arab-American University, Jenin, Palestine
| | - Mahmoud A. Srour
- Department of Medical Laboratory Sciences, Al-Quds University, East Jerusalem, Palestine
- Department of Biology & Biochemistry, Birzeit University, P.O. Box 14, Birzeit, Palestine
| |
Collapse
|
7
|
Ansari S, Rashid N, Hanifa A, Siddiqui S, Kaleem B, Naz A, Perveen K, Hussain Z, Ansari I, Jabbar Q, Khan T, Nadeem M, Shamsi T. Laboratory diagnosis for thalassemia intermedia: Are we there yet? J Clin Lab Anal 2019; 33:e22647. [PMID: 30221402 PMCID: PMC6430353 DOI: 10.1002/jcla.22647] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 07/12/2018] [Accepted: 07/20/2018] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Differentiation between thalassemia major and thalassemia intermedia at presentation is not uniformly characterized, for which an absolute criteria needs to be developed. This study investigated the primary and secondary genetic modifiers to develop a laboratory finding by forming different genetic mutational combinations seen among thalassemia intermedia patients and comparing them with thalassemia major. METHODS This cross-sectional study analyzed 315 thalassemia intermedia patients. One hundred and five thalassemia major patients were recruited on the basis of documented evidence of diagnosis and were receiving blood transfusion therapy regularly. Various mutational combinations were identified, and comparison was performed between thalassemia intermedia and major using statistical software STATA 11.1. RESULTS The mean age of the total population was 5.9 ± 5.32 years of which 165 (52%) were males. Of the two groups (thalassemia intermedia and thalassemia major), IVSI-5, IVSI-1, and Fr 8-9 were more prevalent among the thalassemia intermedia cohort. When comparison was performed between the thalassemia intermedia and thalassemia major patients, it showed significant results for the presence of Xmn-1 polymorphism. CONCLUSION The presence of IVSI-5 homozygous with Xmn-1, IVSI-5 heterozygous with Xmn-1, Cd 30 homozygous with or without Xmn-1 and IVSI-1 homozygous or heterozygous either with or without Xmn-1 prove to be strong indicators towards diagnosis of thalassemia intermedia.
Collapse
Affiliation(s)
- Saqib Ansari
- Department of HaematologyNational Institute of Blood Diseases & BMTKarachiPakistan
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Nabil Rashid
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Anny Hanifa
- Department of HaematologyNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Saima Siddiqui
- Department of HaematologyNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Bushra Kaleem
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Arshi Naz
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Kousar Perveen
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Zeeshan Hussain
- Department of HaematologyNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Iqra Ansari
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Qammar Jabbar
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Tahir Khan
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Muhammad Nadeem
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| | - Tahir Shamsi
- Department of HaematologyNational Institute of Blood Diseases & BMTKarachiPakistan
- Department of ResearchNational Institute of Blood Diseases & BMTKarachiPakistan
| |
Collapse
|
8
|
Hassan T, Zakaria M, Fathy M, Arafa M, El Gebaly S, Emam A, Abdel Wahab A, Shehab M, Salah H, Malek M, El Gerby K. Association between genotype and disease complications in Egyptian patients with beta thalassemia: A Cross-sectional study. Sci Rep 2018; 8:17730. [PMID: 30531823 PMCID: PMC6286337 DOI: 10.1038/s41598-018-36175-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Accepted: 11/11/2018] [Indexed: 01/19/2023] Open
Abstract
In beta thalassemia, the degree of globin chain imbalance is determined by the nature of the mutation of the β-gene. β° refers to the complete absence of production of β-globin on the affected allele. β+ refers to alleles with some residual production of β-globin. The homozygous state results in severe anemia that necessitates regular blood transfusion. On the other hand, frequent blood transfusion can lead to iron overload resulting in progressive dysfunction of the heart, Liver as well as multiple endocrinopathies. We studied the impact of genotype on the development of disease complications in patients with β thalassemia. A Cross sectional study was carried on 73 patients with beta thalassemia. Genotyping was determined by DNA sequencing technique. Routine investigations as well as MRI liver and heart were performed to assess iron overload. We found that β+β+ was the most common genotype in our patients followed by β°β° and β°β+. Mean Liver iron content (LIC) was significantly higher in β°β° compared to β°β+ and β+β+ genotypes and mean cardiac T2* was significantly lower in β°β° compared to β°β+ and β+β+ genotypes. Hepatic complications, hepatitis C, cardiac complications and some endocrinopathies were significantly higher in patients with β°β° genotype compared to other genotypes which explain the role of the underlying genetic defect in thalassemia patients in development of disease complications.
Collapse
Affiliation(s)
| | | | - Manar Fathy
- Pediatric, Zagazig University, Zagazig, Egypt
| | | | | | - Ahmed Emam
- Pediatric, Zagazig University, Zagazig, Egypt
| | | | | | - Hosam Salah
- Clinical pathology, Zagazig University, Zagazig, Egypt
| | - Mai Malek
- Microbiology, Zagazig University, Zagazig, Egypt
| | - Khaled El Gerby
- Radiodiagnosis departments, Zagazig University, Zagazig, Egypt
| |
Collapse
|
9
|
Hassan TH, Salam MMA, Zakaria M, Shehab M, Sarhan DT, Zidan ESH, El Gerby KM. Impact of Genotype of Beta Globin Gene on Hepatic and Myocardial Iron Content in Egyptian Patients with Beta Thalassemia. Indian J Hematol Blood Transfus 2018; 35:284-291. [PMID: 30988565 DOI: 10.1007/s12288-018-1034-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 10/24/2018] [Indexed: 01/19/2023] Open
Abstract
Iron overload causes most of the mortality and morbidity associated with thalassemia. Excess iron deposits primarily in the liver, but once a threshold level is reached, iron loading may occur in other tissues such as the heart. Magnetic resonance imaging is a well established technique to noninvasively quantify myocardial and liver iron content. More than 300 disease-causing mutations have been identified. We aimed to determine the impact of genotype on liver iron content in patients with beta thalassemia. Cross sectional study was carried on 73 patients with beta thalassemia. MRI liver and heart was performed to determine hepatic and myocardial iron overload. Genotyping was determined by DNA sequencing technique. The mean liver iron content was 17.4 mg/g dw and mean cardiac T2* was 25.5 ms in our patients. Patients with β0β0 were associated with significantly higher liver and myocardial iron content compared to those with β0β+ and β+β+ genotypes. There was a clear association between genotype and both hepatic and myocardial iron overload. Patients with β0β0 had significantly higher liver and heart iron content compared to those with β0β+ and β+β+ genotypes. Liver iron content was strongly correlated to serum ferritin levels and myocardial iron overload.
Collapse
Affiliation(s)
- Tamer H Hassan
- 1Pediatric Department, Faculty of Medicine, Zagazig University, Zagazig, 44111 Egypt
| | - Mohamed M Abdel Salam
- 1Pediatric Department, Faculty of Medicine, Zagazig University, Zagazig, 44111 Egypt
| | - Marwa Zakaria
- 1Pediatric Department, Faculty of Medicine, Zagazig University, Zagazig, 44111 Egypt
| | - Mohamed Shehab
- 1Pediatric Department, Faculty of Medicine, Zagazig University, Zagazig, 44111 Egypt
| | - Dina T Sarhan
- 1Pediatric Department, Faculty of Medicine, Zagazig University, Zagazig, 44111 Egypt
| | | | | |
Collapse
|
10
|
Evaluation of the Clinical and Laboratory Characteristics of Previously Followed-up Thalassemia Intermedia Patients to Provide Them Better Care in the Future. J Pediatr Hematol Oncol 2017; 39:440-444. [PMID: 28719510 DOI: 10.1097/mph.0000000000000914] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
The increased awareness about the severity of complications in thalassemia intermedia patients led authorities to develop strategies for better management and follow-up of these patients. In this study, we aimed to define the clinical and laboratory characteristics in previously followed-up β-thalassemia intermedia patients and wanted to gain an insight about the follow-up of this patient population in a developing country to provide them better care in the future. The mean age at diagnosis was 4 years, and the mean hemoglobin was 7.13 g/dL. The mean age at the beginning of regular transfusion was 4.8 years. An overall 74% of patients were on a regular transfusion program. The mean ferritin values at diagnosis and the last follow-up were 487 and 1225 ng/mL, respectively. The most common mutations detected in patients were IVS-I-110, IVS-I-6, IVS-II-1, and FCS 8/9 in order of frequency. Complications were seen in 48% of patients. The most common complications were osteopenia/osteoporosis (34%), growth retardation (24%), hypogonadism (18%), and cardiomyopathy (13%). In conclusion, the relatively higher complication rate in our patients who were previously treated highlights once again the need for an increased effort for optimal management and follow-up of this specific group of patients.
Collapse
|
11
|
Ben Salah N, Bou-Fakhredin R, Mellouli F, Taher AT. Revisiting beta thalassemia intermedia: past, present, and future prospects. ACTA ACUST UNITED AC 2017; 22:607-616. [PMID: 28589785 DOI: 10.1080/10245332.2017.1333246] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND The spectrum of thalassemias is wide ranging from thalassemia minor, which consists of mild hypochromic microcytic anemia without obvious clinical manifestations, to thalassemia major (TM), which is characterized by severe anemia since the first years of life and is transfusion dependent. Thalassemia intermedia (TI) describes those patients with mild or moderate anemia. OBJECTIVE To describe the genetic features and major clinical complications of TI, and the therapeutic approaches available in the management of this disease. METHODS Publications from potentially relevant journals were searched on Medline. RESULTS AND DISCUSSION Over the past decade, the understanding of TI has increased with regard to pathophysiology and molecular studies. It is now clear that clinical presentation and specific complications make TI different from TM. It is associated with greater morbidity, a wider spectrum of organ dysfunction and more complications than previously thought. CONCLUSION TI is not a mild disease. The interplay of three hallmark pathophysiologic factors (ineffective erythropoiesis, chronic anemia, and iron overload) leads to the clinical presentations seen in TI. New treatment modalities are currently being investigated to broaden the options available for TI management.
Collapse
Affiliation(s)
- Naouel Ben Salah
- a Faculty of Medicine Tunis , University Tunis El Manar , Tunis, Tunisia
| | - Rayan Bou-Fakhredin
- b Department of Internal Medicine , American University of Beirut Medical Center , Beirut , Lebanon
| | - Fethi Mellouli
- c Faculty of Medicine Tunis, National Center of Bone Marrow Graft , University Tunis El Manar , Tunis , Tunisia
| | - Ali T Taher
- b Department of Internal Medicine , American University of Beirut Medical Center , Beirut , Lebanon
| |
Collapse
|
12
|
Platelet haemostatic properties in β-thalassaemia: the effect of blood transfusion. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2016; 15:413-421. [PMID: 27723451 DOI: 10.2450/2016.0033-16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 06/16/2016] [Indexed: 11/21/2022]
Abstract
BACKGROUND Patients with thalassaemia may have thromboembolic events and, even without thrombosis, they have a subclinical hypercoagulable state. In this setting, several coagulation laboratory abnormalities have been described, but thus far no studies have explored the contribution of platelet adhesive and procoagulant properties to blood clotting activation. In this study, we dissected the platelet procoagulant effect and influence of blood transfusions on haemostasis and platelet function in thalassaemic patients. MATERIAL AND METHODS Sixteen subjects with thalassaemia were studied (9 with transfusion-dependent β-thalassaemia, 7 "trait" carriers). Splenectomised and non-splenectomised patients undergoing blood transfusion were compared. All splenectomised patients were then compared to "trait" carriers and to healthy controls (n=9). The following parameters were measured in transfusion-dependent patients before and after monthly transfusions and compared to those of controls: levels of platelet surface activation markers (P-selectin, tissue factor, and fibrinogen), whole blood platelet aggregation, tissue factor or adenosine diphosphate (ADP)-induced platelet thrombin generation (TG) potential, and D-dimer. RESULTS Before transfusion, platelets from splenectomised patients showed significantly higher ADP-induced tissue factor expression, ADP- and collagen-induced platelet aggregation and TG potential than those from non-splenectomised patients and controls. Blood transfusion in splenectomised patients reduced platelet activation, aggregation and TG potential. DISCUSSION Splenectomised patients with β-thalassaemia had a prothrombotic state, characterised by enhanced platelet reactivity and function, and high platelet-induced TG potential. One hour after blood transfusions platelet and coagulation parameters improved, supporting the hypothesis that transfusion might have a protective role on platelet haemostatic status.
Collapse
|
13
|
Mettananda S, Gibbons RJ, Higgs DR. Understanding α-globin gene regulation and implications for the treatment of β-thalassemia. Ann N Y Acad Sci 2015; 1368:16-24. [PMID: 26695885 DOI: 10.1111/nyas.12988] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Over the past three decades, a vast amount of new information has been uncovered describing how the globin genes are regulated. This knowledge has provided significant insights into the general understanding of the regulation of human genes. It is now known that molecular defects within and around the α- and β-globin genes, as well as in the distant regulatory elements, can cause thalassemia. Unbalanced production of globin chains owing to defective synthesis of one, and the continued unopposed synthesis of another, is the central causative factor in the cellular pathology and pathophysiology of thalassemia. A large body of clinical, genetic, and experimental evidence suggests that altering globin chain imbalance by reducing the production of α-globin synthesis ameliorates the disease severity in patients with β-thalassemia. With the development of new genetic-based therapeutic tools that have a potential to decrease the expression of a selected gene in a tissue-specific manner, the possibility of decreasing expression of the α-globin gene to improve the clinical severity of β-thalassemia could become a reality.
Collapse
Affiliation(s)
- Sachith Mettananda
- Medical Research Council (MRC) Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.,Department of Pediatrics, Faculty of Medicine, University of Kelaniya, Sri Lanka
| | - Richard J Gibbons
- Medical Research Council (MRC) Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom
| | - Douglas R Higgs
- Medical Research Council (MRC) Molecular Hematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, United Kingdom.,Oxford National Institute for Health Research Biomedical Research Centre, Blood Theme, Oxford University Hospital, Oxford, United Kingdom
| |
Collapse
|
14
|
Prevalence and Risk Factors for Complications in Patients with Nontransfusion Dependent Alpha- and Beta-Thalassemia. Anemia 2015; 2015:793025. [PMID: 26664743 PMCID: PMC4667021 DOI: 10.1155/2015/793025] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2015] [Accepted: 11/05/2015] [Indexed: 01/27/2023] Open
Abstract
Background. Nontransfusion dependent thalassemia (NTDT) is a milder form of thalassemia that does not require regular transfusion. It is associated with many complications, which differ from that found in transfusion-dependent thalassemia (TDT). Currently available information is mostly derived from beta-NTDT; consequently, more data is needed to describe complications found in the alpha-NTDT form of this disease. Methods. We retrospectively reviewed the medical records of NTDT patients from January 2012 to December 2013. Complications related to thalassemia were reviewed and compared. Results. One hundred patients included 60 females with a median age of 38 years. The majority (54 patients) had alpha-thalassemia. Overall, 83 patients had one or more complications. The three most common complications were cholelithiasis (35%), abnormal liver function (29%), and extramedullary hematopoiesis (EMH) (25%). EMH, cardiomyopathy, cholelithiasis, and pulmonary hypertension were more commonly seen in beta-thalassemia. Osteoporosis was the only complication that was more common in alpha-thalassemia. The risk factors significantly related to EMH were beta-thalassemia type and hemoglobin < 8 g/dL. The risk factors related to osteoporosis were female gender and age > 40 years. Iron overload (ferritin > 800 ng/mL) was the only risk factor for abnormal liver function. Conclusion. The prevalence of alpha-NTDT complications was lower and different from beta-thalassemia.
Collapse
|
15
|
α-Globin as a molecular target in the treatment of β-thalassemia. Blood 2015; 125:3694-701. [PMID: 25869286 DOI: 10.1182/blood-2015-03-633594] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2015] [Accepted: 03/31/2015] [Indexed: 12/31/2022] Open
Abstract
The thalassemias, together with sickle cell anemia and its variants, are the world's most common form of inherited anemia, and in economically undeveloped countries, they still account for tens of thousands of premature deaths every year. In developed countries, treatment of thalassemia is also still far from ideal, requiring lifelong transfusion or allogeneic bone marrow transplantation. Clinical and molecular genetic studies over the course of the last 50 years have demonstrated how coinheritance of modifier genes, which alter the balance of α-like and β-like globin gene expression, may transform severe, transfusion-dependent thalassemia into relatively mild forms of anemia. Most attention has been paid to pathways that increase γ-globin expression, and hence the production of fetal hemoglobin. Here we review the evidence that reduction of α-globin expression may provide an equally plausible approach to ameliorating clinically severe forms of β-thalassemia, and in particular, the very common subgroup of patients with hemoglobin E β-thalassemia that makes up approximately half of all patients born each year with severe β-thalassemia.
Collapse
|
16
|
Al-Allawi NAS, Puehringer H, Raheem RA, Oberkanins C. Genetic Modifiers in β-Thalassemia Intermedia: A Study on 102 Iraqi Arab Patients. Genet Test Mol Biomarkers 2015; 19:242-7. [PMID: 25751242 DOI: 10.1089/gtmb.2014.0310] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
To determine the molecular basis of β-thalassemia intermedia (TI) and the contribution of the three hemoglobin F (HbF) quantitative trait loci (QTLs) on chromosomes 11, 2, and 6 to the milder phenotype, a total of 102 Iraqi Arab patients with TI were studied. The β and α genotypes as well as HBG2 g. 158 C>T (rs7482144), BCL11A (rs1427407 and rs10189857), and HBS1L-MYB (rs28384513 and rs9399137) by multiplex polymerase chain reaction and reverse hybridization were studied. A total of 21 different β-thalassemia mutations arranged in 35 different genotypes were identified. The genotypes encompassed β(+)/β(+) mutations in 33 cases, β(+)/β(0) in 17 cases, β(0)/β(0) in 47 cases, β(0)/wild type in 3 and β(0)/Hb E in 2 cases. The most common was IVS-II-1 (G>A)/IVS-II-1 (G>A), followed by IVS-I-6 (T>C)/IVS-I-6 (T>C) and IVS-I-110 (G>A)/IVS-I-110 (G>A), in 31.4%, 17.6%, and 6.9%, respectively. Alpha-thalassemia mutations were found in 15.2% of those homozygous for the β-mutations, while α gene triplication was identified in all three heterozygotes. Of the five QTLs tested, only rs7482144 and rs10189857 were significantly associated with β(0)/β(0) when compared to β(+)/β(+), with odds ratios of 6.4 (95% confidence interval [CI] 2.9-14.0) and 3.2 (95% CI 1.2-8.6), respectively. In conclusion, this study has demonstrated that among Iraqi patients with thal intermedia, the main contributors to the milder phenotype were β(+) alleles, XmnI polymorphism, and BCL11A (rs10189857), while other QTLs on chromosomes 2 and 6, as well as alpha-thalassemia, were not significantly relevant.
Collapse
Affiliation(s)
- Nasir A S Al-Allawi
- 1 Faculty of Medical Sciences, Scientific Research Center, University of Duhok , Duhok, Iraq
| | | | | | | |
Collapse
|
17
|
Pereira C, Relvas L, Bento C, Abade A, Ribeiro ML, Manco L. Polymorphic variations influencing fetal hemoglobin levels: association study in beta-thalassemia carriers and in normal individuals of Portuguese origin. Blood Cells Mol Dis 2015; 54:315-20. [PMID: 25842369 DOI: 10.1016/j.bcmd.2015.02.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 02/13/2015] [Accepted: 02/14/2015] [Indexed: 01/03/2023]
Abstract
Three major loci have been associated with HbF levels, including -158C/T (XmnI) at HBG2 promoter region, and several polymorphisms at BCL11A intron-2 and HBS1L-MYB (HMIP) intergenic region. Mutations in the KLF1 gene were recently associated with increased HbF levels. This study aims to evaluate whether genetic variability at these loci influences HbF levels in β-thalassemia carriers and in normal individuals of Portuguese origin. Sixty five β-thalassemia carriers, HbF levels ranging from 0.2% to 9.5%, and 60 individuals with normal hematological parameters, HbF levels ranging from 0.2% to 7.4%, were selected for this study. In β-thal carriers linear regression models revealed a strong statistical significant association for HBG2 (XmnI) rs7482144 (β=0.455; P=5.858×10(-7)), and nominal significance for BCL11A rs766432 (β=0.215; P=0.029) and HMIP rs9399137 (β=0.209; P=0.011). In normal individuals, a case (HbF>2%; n=15) vs. control (HbF<1.7%; n=45) model, showed nominal significant associations for BCL11A SNPs rs11886868 (OR=4; P=0.001), rs766432 (OR=3.7; P=0.002) and rs7606173 (OR=0.36; P=0.032). KLF1 rs3817621 was not found associated with HbF levels. Our results suggest that in Portuguese β-thal carriers the HBG2 XmnI polymorphism is strongly associated with HbF levels. In normal individuals, BCL11A polymorphisms, but not HMIP or HBG2 (XmnI) loci, are nominally associated with HbF expression.
Collapse
Affiliation(s)
- Clara Pereira
- Research Centre for Anthropology and Health (CIAS), Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - Luís Relvas
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Celeste Bento
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Augusto Abade
- Research Centre for Anthropology and Health (CIAS), Department of Life Sciences, University of Coimbra, Coimbra, Portugal
| | - M Letícia Ribeiro
- Department of Hematology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal
| | - Licínio Manco
- Research Centre for Anthropology and Health (CIAS), Department of Life Sciences, University of Coimbra, Coimbra, Portugal; Department of Hematology, Centro Hospitalar e Universitário de Coimbra (CHUC), Coimbra, Portugal.
| |
Collapse
|
18
|
β -thalassemia intermedia in Northern Iraq: a single center experience. BIOMED RESEARCH INTERNATIONAL 2014; 2014:262853. [PMID: 24719849 PMCID: PMC3955643 DOI: 10.1155/2014/262853] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 11/17/2013] [Revised: 01/18/2014] [Accepted: 01/20/2014] [Indexed: 12/20/2022]
Abstract
To investigate the molecular basis of β-thalassemia intermedia in Northern Iraq and evaluate its management practices, a total of 74 patients from 51 families were enrolled. The patients were clinically and hematologically reevaluated, and had their β-thalassemia mutations characterized, as well as the number of α-globin genes and Xmn I Gγ −158 (C>T) polymorphism studied. Out of 14 β-thalassemia mutations identified, the four most common were IVS-I-6 (T>C) [33.3%], IVS-II-I (G>A) [21.1%], codon 82/83(−G) [10.1%], and codon 8 (−AA) [8.1%]. The most common contributing factors to the less severe phenotype of thalassemia intermedia were found to be the inheritance of mild β-thalassemia alleles and the Xmn I polymorphism, while concomitant α-thalassemia had a limited role. Several complications were documented including: pulmonary hypertension in 20.4%, diabetes mellitus in 1.4%, hypothyroidism in 2.9%, and heart failure in 2.7%, while no documented cases of venous thrombosis were found. Compared to their counterparts in several Mediterranean countries, it appears that our patients were much less frequently transfused and had a lower proportion of patients who were splenectomized, on iron chelation, or hydroxycarbamide therapy. Such practices require further scrutiny to ensure that a better level of care is provided and that growth retardation, skeletal changes, and other complications are prevented or reduced.
Collapse
|
19
|
Jouini L, Sahli CA, Laaouini N, Ouali F, Youssef IB, Dakhlaoui B, Othmeni R, Ouennich F, Fredj SH, Siala H, Becher M, Toumi NE, Fattoum S, Hafsia R, Bibi A, Messaoud T. Association between clinical expression and molecular heterogeneity in β-thalassemia Tunisian patients. Mol Biol Rep 2013; 40:6205-12. [DOI: 10.1007/s11033-013-2732-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2012] [Accepted: 09/14/2013] [Indexed: 10/26/2022]
|
20
|
Panigrahi I, Agarwal S. Genetic determinants of phenotype in beta-thalassemia. Hematology 2013; 13:247-52. [DOI: 10.1179/102453308x316031] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022] Open
Affiliation(s)
- Inusha Panigrahi
- Department of PediatricsPostgraduate Institute of Medical Education and Research, Chandigarh-12, India
| | - Sarita Agarwal
- Department of Medical GeneticsSanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow-14, India
| |
Collapse
|
21
|
|
22
|
Payen E, Colomb C, Negre O, Beuzard Y, Hehir K, Leboulch P. Lentivirus Vectors in β-Thalassemia. Methods Enzymol 2012; 507:109-24. [DOI: 10.1016/b978-0-12-386509-0.00006-5] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
23
|
Jouini L, Bibi A, Ouali F, Hadj Fredj S, Ouennich F, Siala H, Messaoud T, Fattoum S. Contribution of β-globin cluster polymorphisms to raise fetal hemoglobin levels in normal adults. Mol Biol Rep 2011; 39:4619-25. [DOI: 10.1007/s11033-011-1253-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2010] [Accepted: 09/14/2011] [Indexed: 11/30/2022]
|
24
|
Xie SY, Li W, Ren ZR, Huang SZ, Zeng F, Zeng YT. Correction of β654-thalassaemia mice using direct intravenous injection of siRNA and antisense RNA vectors. Int J Hematol 2011; 93:301-310. [PMID: 21369857 DOI: 10.1007/s12185-010-0727-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2010] [Revised: 10/27/2010] [Accepted: 11/10/2010] [Indexed: 01/17/2023]
Abstract
Although the therapeutic efficacy of β(654)-thalassaemia treatment using a combination of RNAi and antisense RNA to balance the synthesis of α- and β-globin chains has been demonstrated previously, and the safety of lentiviral delivery remains unclear. Herein, we used the same β(654)-thalassaemia mouse model to develop a therapy involving direct delivery of siRNA and antisense RNA plasmids via intravenous injection to simultaneously knock down α-globin transcript levels and restore correct β-globin splicing. The amount of α-globin mRNAs in siRNA-treated MEL cells decreased significantly, and the properly spliced β-globin mRNA was restored in HeLaβ(654) cells transfected with pcDNA-antisense plasmid. Furthermore, treatment of β(654)-thalassaemic mice with siRNA and antisense RNA plasmids resulted in significant reduction of poikilocytosis and reticulocyte counts in blood samples, decreased nucleated cell populations in bone marrow, and reduced intrasinusoidal extramedullary haematopoiesis loci and iron accumulation in liver. RT-PCR analysis revealed that treatment resulted in down-regulation of α-globin mRNA synthesis by ~50% along with an increase in the presence of normally spliced β-globin transcripts, indicating that the phenotypic changes observed in β(654)-thalassaemic mice following treatment resulted from restoration of the balance of α/β-globin biosynthesis.
Collapse
Affiliation(s)
- Shu-Yang Xie
- Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai, 200040, People's Republic of China
| | - Wei Li
- Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai, 200040, People's Republic of China
| | - Zhao-Rui Ren
- Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai, 200040, People's Republic of China
- Key Lab of Medical Embryo Molecular Biology, Ministry of Health, China, Shanghai Lab of Embryo and Reproduction Engineering, Shanghai, People's Republic of China
| | - Shu-Zhen Huang
- Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai, 200040, People's Republic of China
- Key Lab of Medical Embryo Molecular Biology, Ministry of Health, China, Shanghai Lab of Embryo and Reproduction Engineering, Shanghai, People's Republic of China
| | - Fanyi Zeng
- Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai, 200040, People's Republic of China.
- Key Lab of Medical Embryo Molecular Biology, Ministry of Health, China, Shanghai Lab of Embryo and Reproduction Engineering, Shanghai, People's Republic of China.
- Institute of Medical Science, Shanghai Jiao Tong University School of Medicine, Shanghai, People's Republic of China.
| | - Yi-Tao Zeng
- Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, Shanghai Jiao Tong University School of Medicine, 24/1400 West Beijing Road, Shanghai, 200040, People's Republic of China.
- Key Lab of Medical Embryo Molecular Biology, Ministry of Health, China, Shanghai Lab of Embryo and Reproduction Engineering, Shanghai, People's Republic of China.
| |
Collapse
|
25
|
Broquere C, Brudey K, Harteveld CL, Saint-Martin C, Elion J, Giordano PC, Romana M. Phenotypic expression and origin of the rare beta-thalassemia splice site mutation HBB:c.315 + 1G>T. Hemoglobin 2010; 34:322-6. [PMID: 20524821 DOI: 10.3109/03630269.2010.484956] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
We present the hematological characteristics of five patients from Surinam and the bordering French Guyana, who are carriers of the rare beta-thalassemia (beta-thal) mutation HBB:c.315+1G>T. Analysis of the phenotype/genotype relationship shows that this allele is a beta(0)-thal variant and illustrates the modulating effect of the alpha-globin gene status on the beta-thal phenotype. The ethnic origin of the five probands, belonging to the so-called Bush Negroes Maroons of Surinam and French Guyana, strongly suggests that this beta-thal mutation has a West African origin and spread in this ethnic group because of a founder effect and/or genetic drift.
Collapse
Affiliation(s)
- Cédrick Broquere
- INSERM U763, Université des Antilles et de la Guyane, Pointe-à-Pitre, Guadeloupe, France
| | | | | | | | | | | | | |
Collapse
|
26
|
Cappellini MD, Musallam KM, Taher AT. Insight onto the pathophysiology and clinical complications of thalassemia intermedia. Hemoglobin 2010; 33 Suppl 1:S145-59. [PMID: 20001620 DOI: 10.3109/03630260903351528] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Our understanding of the molecular and pathophysiological mechanisms underlying the disease process in patients with thalassemia intermedia (TI) has substantially increased over the past decade. TI encompasses a wide clinical spectrum of beta-thalassemia phenotypes. Some TI patients are asymptomatic until adult life, whereas others are symptomatic from as young as 2 years. A number of clinical complications commonly associated with TI are rarely seen in thalassemia major, including extramedullary hematopoiesis, leg ulcers, gallstones, thrombosis, and pulmonary hypertension. There are a number of options currently available for managing patients with TI, including transfusion therapy, iron chelation therapy, modulation of fetal hemoglobin production, and hematopoietic stem cell transplantation. However, at present, there are no clear guidelines for an orchestrated optimal treatment plan.
Collapse
|
27
|
Abstract
The hemoglobin disorders serve as a model for study of the genetic heterogeneity underlying the phenotype of genetic disorders. 'Thalassemia intermedia' is a clinical phenotype which displays marked genotypic variability in different populations or ethnic groups. Two common underlying mechanisms include co-inheritance of alpha globin gene deletions in homozygous thalassemia intermedia and presence of XmnI polymorphism. The newly described mechanisms including unstable hemoglobin disorders and somatic deletions in beta-globin gene are elaborated in the present review.
Collapse
Affiliation(s)
- Inusha Panigrahi
- Department of Pediatrics, Advanced Pediatric Centre, Postgraduate Institute of Medical Education and Research, Chandigarh-12, India.
| | | | | |
Collapse
|
28
|
Thalassaemia intermedia: an update. Mediterr J Hematol Infect Dis 2009; 1:e2009004. [PMID: 21415986 PMCID: PMC3033165 DOI: 10.4084/mjhid.2009.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2009] [Accepted: 08/19/2009] [Indexed: 01/29/2023] Open
Abstract
Our understanding of the molecular and pathophysiological mechanisms underlying the disease process in patients with thalassaemia intermedia (TI) has substantially increased over the past decade. TI encompasses a wide clinical spectrum of beta-thalassaemia phenotypes. Some TI patients are asymptomatic until adult life, whereas others are symptomatic from as young as 2 years of age. A number of clinical complications commonly associated with TI are rarely seen in thalassaemia major, including extramedullary hematopoiesis, leg ulcers, gallstones, thrombosis and pulmonary hypertension. There are a number of options currently available for managing patients with TI, including transfusion therapy, iron chelation therapy, modulation of foetal haemoglobin production and haematopoietic stem cell transplantation. However, at present, there are no clear guidelines for an orchestrated optimal treatment plan.
Collapse
|
29
|
Lemsaddek W, Picanço I, Seuanes F, Nogueira P, Mahmal L, Benchekroun S, Khattab M, Osório-Almeida L. The β‐Thalassemia Mutation/Haplotype Distribution in the Moroccan Population. Hemoglobin 2009; 28:25-37. [PMID: 15008262 DOI: 10.1081/hem-120028884] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
The present study compiles the results of our own research and of a prior study on beta-thalassemia (thal) in Morocco, comprising a total of 187 beta-thalassemic chromosomes. Six major mutations: (beta0) codon 39 (C --> T), (beta+) IVS-I-6 (T --> C), (beta0) frameshift codon (FSC) 6 (-A), (beta0) FSC 8 (-AA), (beta0) IVS-I-1 (G --> A) and (beta+) -29 (A --> G) account for 75.7% of the independent chromosomes studied. A regional predominance was observed (Gharb and West regions) for the (beta+) IVS-I-6 (T --> C) mutation. Despite an observed heterogeneity of molecular anomalies, a direct method of diagnosis of the prevalent mutations is feasible in this population. The distributions of mutations and haplotypes are in conformity with the geographical location of Morocco and the historical links with both the Mediterranean communities that have successively interspersed with the Berbers, the Phoenicians, the Carthaginians, the Romans, the Arabs, the population of the Iberian Peninsula and, to a lesser degree, the Vandals and the Byzantines and permanently, with the Sub-Saharan Africans. In the adult population, the levels of fetal hemoglobin (Hb) in heterozygotes vary from trace quantities to 2.38 g/dL of total Hb. With the exception of the (beta0) codon 39 (C --> T) nonsense mutation, no statistically significant correlation was found, neither between mutation and Hb F levels, nor gender and Hb F levels in heterozygotes. The genetic markers for Hb F increase, located within cis active sites such as the XmnI site at -158 bp of the Ggamma-globin gene and the AT(X)T(Y) repeat region at -540 bp of the beta-globin gene, were assessed. The polymorphism XmnI shows linkage disequilibrium with haplotypes III, IV and IX, as previously observed in the Algerian, Sicilian and Portuguese beta-thal populations. Contrary to what has previously been reported for a population of beta-thal carriers of European descent, this sample does not show a statistically significant correlation between Hb F levels and the presence of the genetic markers XmnI restriction site at -158 bp of the Ggamma-globin gene and AT(X)T(Y) alleles at 5' of the beta-globin gene.
Collapse
Affiliation(s)
- Wafaâ Lemsaddek
- Laboratório de Genética Molecular, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, Caparica, Portugal
| | | | | | | | | | | | | | | |
Collapse
|
30
|
Verma IC, Kleanthous M, Saxena R, Fucharoen S, Winichagoon P, Raizuddin S, Khan SN, Akbari MT, Izadyar M, Kotea N, Old JM, Ioannou PA, Khan B. Multicenter Study of the Molecular Basis of Thalassemia Intermedia in Different Ethnic Populations. Hemoglobin 2009; 31:439-52. [DOI: 10.1080/03630260701641245] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|
31
|
Kornblit B, Taaning P, Birgens H. β-Thalassemia Due to a Novel Nonsense Mutation at Codon 37 (TGG→TAG) Found in an Afghanistani Family. Hemoglobin 2009; 29:209-13. [PMID: 16114184 DOI: 10.1081/hem-200066319] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
We have identified and characterized a novel beta-thalassemic mutation in an Afghanistanifamily. The molecular pathology consists of a single base substitution (TGG-->TAG) at codon 37 of the beta-globin gene, giving rise to a stop codon (TAG). Premature stop of translation results in a truncated protein and usually the phenotype of beta-thalassemia (thal) major in homozygous individuals. However, this was not the case in our proband, who was homozygous for the codon 37 mutation. He presented with the phenotype of thalassemia intermedia with a hemoglobin (Hb) level of 8.1 g/dL and no previous history of blood transfusions. High performance liquid chromatography (HPLC) analysis showed exclusively Hb F except for a Hb A2 level within normal limits. Subsequent analysis demonstrated homozygosity for the XmnI Ggamma polymorphism and heterozygosity for a deletional alpha-thal (alphaalpha/-alpha(-3.7)). These findings might, at least partly, explain the beta-thal intermedia phenotype observed in the proband.
Collapse
Affiliation(s)
- Brian Kornblit
- Department of Haematology, Herlev University Hospital, Center for Haemoglobin Disorders, Herlev, Denmark
| | | | | |
Collapse
|
32
|
Thein SL, Menzel S. Discovering the genetics underlying foetal haemoglobin production in adults. Br J Haematol 2009; 145:455-67. [DOI: 10.1111/j.1365-2141.2009.07650.x] [Citation(s) in RCA: 151] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
33
|
Cappellini MD, Robbiolo L, Bottasso BM, Coppola R, Fiorelli G, Mannucci APM. Venous thromboembolism and hypercoagulability in splenectomized patients with thalassaemia intermedia. Br J Haematol 2008. [DOI: 10.1111/j.1365-2141.2000.02376.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
34
|
Abstract
Identification of the molecular basis of the beta-thalassaemias and sickle cell disease (SCD) has made it clear that patients with the same beta-globin genotypes can have very variable patterns of clinical expression. Extensive biochemical and pathophysiological studies over the last 50 years have derived two major modifiers--innate ability to produce fetal haemoglobin and co-inheritance of alpha-thalassaemia, subsequently validated by family and population studies. However, these two modifiers do not explain the full clinical spectrum. Genetic studies have been successful in identifying modifiers if the loci have a major clinical effect and if the genetic variants are common. It is possible that additional modifiers could be uncovered using genetic approaches but success will depend on large sample sizes of well-characterised patients with well-defined phenotypes. Since some of the complications, such as overt stroke in SCD, are relatively rare events, intermediate end-points that contribute to the phenotype, such as Transcranial Doppler velocity (a major predictor of stroke in SCD), could be integrated within the genetic analysis. Integrating multiplex genetic testing with clinical and laboratory data to generate predictive models shows potential, but such genetic approaches also require large datasets.
Collapse
Affiliation(s)
- Swee Lay Thein
- King's College London School of Medicine, Department of Haematological Medicine, King's College Hospital, London, UK.
| |
Collapse
|
35
|
Bailey L, Kuroyanagi Y, Franco-Penteado CF, Conran N, Costa FF, Ausenda S, Cappellini MD, Ikuta T. Expression of the gamma-globin gene is sustained by the cAMP-dependent pathway in beta-thalassaemia. Br J Haematol 2007; 138:382-95. [PMID: 17614826 DOI: 10.1111/j.1365-2141.2007.06673.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The present study found that the cyclic adenosine monophosphate (cAMP)-dependent pathway efficiently induced gamma-globin expression in adult erythroblasts, and this pathway plays a role in gamma-globin gene (HBG) expression in beta-thalassaemia. Expression of HBG mRNA increased to about 46% of non-HBA mRNA in adult erythroblasts treated with forskolin, while a cyclic guanosine monophosphate (cGMP) analogue induced HBG mRNA to levels <20% of non-HBA mRNA. In patients with beta-thalassaemia intermedia, cAMP levels were elevated in both red blood cells and nucleated erythroblasts but no consistent elevation was found with cGMP levels. The transcription factor cAMP response element binding protein (CREB) was phosphorylated in nucleated erythroblasts and its phosphorylation levels correlated with HBG mRNA levels of the patients. Other signalling molecules, such as mitogen-activated protein kinases and signal transducers and activators of transcription proteins, were phosphorylated at variable levels and showed no correlations with the HBG mRNA levels. Plasma levels of cytokines, such as erythropoietin, stem cell factor and transforming growth factor-beta were increased in patients, and these cytokines induced both HBG mRNA expression and CREB phosphorylation. These results demonstrate that the cAMP-dependent pathway, the activity of which is augmented by multiple cytokines, plays a role in regulating HBG expression in beta-thalassaemia.
Collapse
Affiliation(s)
- Lakiea Bailey
- Department of Medicine, Institute of Molecular Medicine and Genetics, Medical College of Georgia, Augusta, GA, USA
| | | | | | | | | | | | | | | |
Collapse
|
36
|
Aessopos A, Kati M, Meletis J. Thalassemia intermedia today: should patients regularly receive transfusions? Transfusion 2007; 47:792-800. [PMID: 17465943 DOI: 10.1111/j.1537-2995.2007.01192.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND beta-Thalassemia is an inherited hemoglobin disorder characterized by reduced synthesis of beta-globin chain. The severity of clinical course distinguishes this heterogeneous disease in two main subtypes: thalassemia major (TM) and thalassemia intermedia (TI). TI has a later clinical onset with a milder anemia that does not require transfusions at least during the first few years of life. The clinical picture of TI patients who have not received transfusions or have occasionally received transfusions is dominated by the consequences of chronic hemolytic anemia, tissue hypoxia, and their compensatory reactions, such as bone deformities and fractures, extramedullary hemopoiesis, spleen and liver enlargement, hypercoagulability, and pulmonary hypertension. These complications, especially the latter two, are getting more frequent and severe over the years. Nowadays, although TI patients have almost no changes in the course of the disease, well-treated TM patients with regular transfusion-chelation therapy showed suppression of the anemia-related disorders in parallel to prolongation of life. The new oral iron chelators and the magnetic resonance imaging application for early detection of heart iron load are promising for further improvement on survival. CONCLUSIONS Considering the current cost-benefit balance of regular treatment in TM as well as the frequency and severity of complications in TI, it seems that the majority of TI patients will be benefited if this kind of treatment is applied targeting prevention and not palliation of the anemia-induced complications.
Collapse
Affiliation(s)
- Athanassios Aessopos
- First Department of Internal Medicine, University of Athens Medical School, Laiko General Hospital, Athens, Greece.
| | | | | |
Collapse
|
37
|
Singh SP, Gupta S. Molecular pathogenesis and clinical variability of homozygous beta0-thalassemia in populations of Jammu region of J&K state (India). Hematology 2006; 11:271-5. [PMID: 17178667 DOI: 10.1080/10245330600921956] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
This study was undertaken to evaluate the variation in the clinical presentation of homozygous beta0-thalassemia from severe disease to a beta-thalassemia intermedia phenotype and to look for the contribution of associated factors in this variation of clinical course. Type of beta0-thalassemia mutations, associated alpha-thalassemia, and XmnI polymorphism in the gamma globin gene, which are known to affect the clinical course of the disease, were investigated from 15 homozygous beta0-thalassemia patients comprising 11 patients with beta-thalassemia major and 4 patients with beta-thalassemia intermedia. Transfusion dependency and the age at which the patient presented with symptoms were used to assess the degree of clinical severity of these patients. Three different beta0-thalassemia mutations viz. CD 41-42 (-TTCT), CD 8-9 (+G) and 619 bp deletion, were encountered among the 30 beta-thalassemia alleles. It was observed that the type of beta0-thalassemia mutations was not different between the two groups, but co-inheritance of one or more alpha-gene deletions and the presence of the XmnI polymorphism were associated with lesser severity of the disease.
Collapse
Affiliation(s)
- Suraya Partap Singh
- Department of Zoology, Human Genetic Research Cum Counselling Center, University of Jammu, Jammu, J&K, 180006, India.
| | | |
Collapse
|
38
|
Abstract
The beta-thalassaemias have a major global impact on health and mortality. Allogeneic haemopoietic stem cell transplantation is the only approach that may lead to a cure but this approach is not available to most patients. The mainstay treatment for the majority remains life-long blood transfusion in combination with a rigorous regime of iron chelation. Improved understanding of the pathophysiology and molecular basis of the disease has provided clues for more effective strategies that aim to correct the defect in beta-globin chain synthesis at the primary level or redress the alpha/beta-globin chain imbalance at the secondary level. Improved understanding of the molecular basis of the disease complications, such as iron overloading, has also provided clues for potential molecular targets at the tertiary level.
Collapse
Affiliation(s)
- Lynn Quek
- Department of Haematological Medicine, King's College Hospital, Denmark Hill, London, UK
| | | |
Collapse
|
39
|
Taher A, Isma'eel H, Cappellini MD. Thalassemia intermedia: Revisited. Blood Cells Mol Dis 2006; 37:12-20. [PMID: 16737833 DOI: 10.1016/j.bcmd.2006.04.005] [Citation(s) in RCA: 224] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2006] [Revised: 04/15/2006] [Accepted: 04/17/2006] [Indexed: 12/13/2022]
Abstract
Thalassemia intermedia encompasses a wide clinical spectrum of beta-thalassemia phenotypes. Some thalassemia intermedia patients are asymptomatic until adult life, whereas others are symptomatic from as young as 2 years of age. A number of clinical complications commonly associated with thalassemia intermedia are rarely seen in thalassemia major, including extramedullary hematopoiesis, leg ulcers, gallstones and thrombophilia. Prevention of these complications, possibly with blood transfusion therapy, is ideal since they may be difficult to manage. Currently, many patients with thalassemia intermedia receive only occasional or no transfusions, since they are able to maintain hemoglobin levels between 7-9 g/dl; the risk of iron overload, necessitating adequate chelation therapy, is also a contributing factor. At present, there are no clear guidelines for initiating and maintaining transfusions in thalassemia intermedia for the prevention or treatment of complications. Here, we review the major clinical complications in thalassemia intermedia and suggest some therapeutic strategies based on retrospective clinical observations.
Collapse
Affiliation(s)
- Ali Taher
- Department of Internal Medicine, Hematology-Oncology Division, American University of Beirut Medical Center, Beirut 1107 2020, Lebanon.
| | | | | |
Collapse
|
40
|
Thein SL. Pathophysiology of beta thalassemia--a guide to molecular therapies. HEMATOLOGY. AMERICAN SOCIETY OF HEMATOLOGY. EDUCATION PROGRAM 2005:31-7. [PMID: 16304356 DOI: 10.1182/asheducation-2005.1.31] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
The central mechanism underlying the pathophysiology of the beta thalassemias can be related to the deleterious effects of imbalanced globin chain synthesis on erythroid maturation and survival. An imbalance of the alpha/non-alpha globin chains leads to an excess of unmatched alpha globin which precipitates out, damaging membrane structures leading to accelerated apoptosis and premature destruction of the erythroid precursors in the bone marrow (ineffective erythropoiesis). Close observation of the genotype/phenotype relationships confirms the pathophysiological mechanism and provides clues to molecular therapies, all of which aim to reduce the alpha/non-alpha chain imbalance. They include inheritance of the milder forms of beta thalassemia, co-inheritance of alpha thalassemia, or genetic factors (quantitative trait loci, QTLs) for increasing gamma globin expression. Currently, the most promising molecular therapeutic approaches include increasing beta globin gene expression by stem cell gene therapy and increasing gamma globin expression using pharmacological agents or by transduction of the gamma globin genes.
Collapse
Affiliation(s)
- Swee Lay Thein
- King's College Hospital, Guy's King's & StThomas' School of Medicine, Kings College London, DenmarkHill, London SE5 9PJ, UK.
| |
Collapse
|
41
|
Affiliation(s)
- Swee Lay Thein
- Department of Haematological Medicine, Guy's, King's and St Thomas' School of Medicine, Denmark Hill Campus, Bessemer Road, London SE5 9PJ, UK.
| |
Collapse
|
42
|
Abstract
OBJECTIVE Thalassemia intermedia is an ill-defined group of thalassemia patients with severity in between thalassemia major and asymptomatic carriers. The severity of cases varies greatly. With availability of information about genetic modifiers of beta-thalassemia phenotype, attempts are being made to study genotype phenotype correlation in thalassemia intermedia. METHODS The first important step in genotype, phenotype correlation is well-defined phenotypes. Severity of thalassemia intermedia can not be graded only on haemoglobin level and age of presentation. The authors have developed a phenotype scoring system to subclassify thalassemia intermedia patients into 3 groups, viz, mild, moderate and severe. RESULT This phenotype scoring system appears to grade the severity correctly depending on various clinical features like age of presentation, severity of anaemia, growth retardation, bone marrow hyperplasia, need of blood transfusions and splenectomy. CONCLUSION The classification of thalassemia intermedia will be useful for genotype phenotype correlation, to develop management guidelines for the subgroups and to try new treatment modalities like hydroxyurea, erythropoetin etc.
Collapse
Affiliation(s)
- Shubha R Phadke
- Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
| | | |
Collapse
|
43
|
Thein SL. Beta-thalassaemia prototype of a single gene disorder with multiple phenotypes. Int J Hematol 2002; 76 Suppl 2:96-104. [PMID: 12430908 DOI: 10.1007/bf03165097] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
As the defective genes for more and more genetic disorders become unravelled, it is clear that patients with the same genotype can have many different clinical conditions even in monogenic disorders. The remarkable phenotypic diversity of the beta thalassaemias is prototypical of how the wide spectrum in disease severity can be generated. The most reliable and predictive factor of disease phenotype is the nature of the mutation at the beta-globin locus itself. However, relating phenotype to genotype is complicated by the complex interaction of the environment and other genetic factors at the secondary and tertiary levels, some implicated, and others, as yet unidentified. This article reviews the clinical and haematological diversity encountered in beta thalassaemia and their relationship with the underlying genotypes.
Collapse
Affiliation(s)
- Swee Lay Thein
- Department of Haematological Medicine, Guy's, King's & St Thomas' School of Medicine, London, UK
| |
Collapse
|
44
|
Cighetti G, Duca L, Bortone L, Sala S, Nava I, Fiorelli G, Cappellini MD. Oxidative status and malondialdehyde in beta-thalassaemia patients. Eur J Clin Invest 2002; 32 Suppl 1:55-60. [PMID: 11886433 DOI: 10.1046/j.1365-2362.2002.0320s1055.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND In beta-thalassaemia syndromes, decreased or impaired biosynthesis of beta-globin leads to accumulation of unpaired alpha-globin chains. Moreover, the iron overload in beta-thalassaemia patients generates oxygen-free radicals and peroxidative tissue injury. The aim of this study was to detect and correlate iron overload parameters with the oxidative stress and the antioxidant capability in beta-thalassaemia patients. DESIGN Serum iron, transferrin saturation, serum ferritin, nontransferrin-bound iron (NTBI), levels of serum free and total (free + bound) malondialdehyde (MDA) and total peroxyl radical-trapping antioxidant parameter (TRAP) were evaluated in 21 regularly transfused beta-thalassaemia major (TM) patients, 13 untransfused beta-thalassaemia intermedia (TI) patients and 17 healthy controls. Blood from the TM patients was drawn 48 h after the last desferoxamine (20-40 mg kg(-1)) infusion and just before transfusion. RESULTS Free and total MDA and NTBI levels were higher in the TM patients than in the TI. In the TM patients the free MDA levels correlated positively with serum iron (r = +0.3, P = 0.0006), whereas the total MDA correlated positively with NTBI (r = +0.45, P = 0.037). However, a negative correlation was observed between TRAP and NTBI (r = -0.4, P = 0.0006). In the TI patients there was no significant correlation between free or total MDA and TRAP or NTBI. CONCLUSIONS Our results confirm the peroxidative status generated by iron overload in thalassaemia patients and highlight the rapid formation of marked amounts of free MDA despite the chelation therapy in TM patients.
Collapse
Affiliation(s)
- Giuliana Cighetti
- Department of Medical Chemistry and Biochemistry, Ospedale Maggiore IRCCS, Faculty of Medicine, University of Milan, Via Saldini 50, 20133 Milan, Italy.
| | | | | | | | | | | | | |
Collapse
|
45
|
El-Latif MA, Filon D, Rund D, Oppenheim A, Kanaan M. The beta+-IVS-I-6 (T-->C) mutation accounts for half of the thalassemia chromosomes in the Palestinian populations of the mountain regions. Hemoglobin 2002; 26:33-40. [PMID: 11939510 DOI: 10.1081/hem-120002938] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
A study of the spectrum of beta-thalassemia mutations in the southern part of the West Bank of the Palestinian Authority revealed the presence of 10 different beta-globin mutations. The study included 41 patients and 54 carriers of beta-thalassemia and sickle cell anemia. The spectrum of mutations observed was typically Mediterranean. However, their relative frequencies was unique. The predominant allele was IVS-I-6 (T-->C), with an exceptionally high frequency of 48.5% for this mutation. The homozygous IVS-I-6 patients had widely variable clinical presentations, from typical transfusion-dependent thalassemia major to non-transfusion-dependent thalassemia intermedia phenotype. Since it is so widespread in these West Bank populations, the IVS-I-6 mutation may date back to ancient times. The nonsense mutation at codon 37 (G-->A) was found at a relatively high frequency of 11.3%, supporting the hypothesis that it originated in this region. The other mutations, at decreasing frequencies ranging from 9.5-1.5%, were: IVS-I-110 (G-->A), frameshift codon 5 (- CT), IVS-I-1 (G-->A), IVS-II-1 (G-->A), Hb S [beta6(A3)Glu-->Val], frameshift codons 8/9 (+G), codon 39 (C-->T), and -30 (T-->A). Our findings will improve health care for the Palestinian population, and also has implications for the study of the origin and spread of thalassemia in the Middle East.
Collapse
|
46
|
Rigoli L, Meo A, Miceli MR, Alessio K, Caruso RA, La Rosa MA, Salpietro DC, Ricca M, Barberi I. Molecular analysis of beta-thalassaemia patients in a high incidence area of southern Italy. CLINICAL AND LABORATORY HAEMATOLOGY 2001; 23:373-8. [PMID: 11843884 DOI: 10.1046/j.1365-2257.2001.00367.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The prevalence of eight mutations in 84 patients with beta-thalassaemia major and in 16 subjects with thalassaemia intermedia was investigated. All of the patients were Italian, originating from Eastern Sicily (Messina area) and some Calabrian regions. Genomic DNA was amplified by polymerase chain reaction (PCR). DNA molecular investigations were performed by allele-specific oligonucleotide (ASO) hybridization, to identify the following beta-thalassaemia mutations: CD39 (C-T), IVS1-110 (G-A), IVS1-6 (T-C), IVS1-1 (G-A), IVS2-745 (C-G), IVS2-1 (G-A), -87 (C-G), CD6 A (-A). Our data underline that in thalassemia intermedia two mutations were statistically prevalent: IVS1-6 T-->C (P < 0.001) and CD 6-A (P < 0.05). CD 39 was statistically prevalent in beta-thalassaemia major patients (P < 0.01). The difference between the two groups was not statistically significant for all the other mutations. Five different genotypes were recorded among thalassaemia intermedia and 15 among beta-thalassaemia major patients. Twenty-five percent of the intermedia patients and 4.5% of the major patients had homozygosity for mild mutations (group I); 62.5% of the intermedia patients and 26.2% of the major patients had combinations of mild/severe mutations (group II). In addition, homozygosity or double heterozygosity for severe mutations (group III) was found in 12.5% of the intermedia patients and 69% of the major patients. Some genotypes were restricted to thalassaemia intermedia, including heterozygosity -87/IVS1-6 and IVS1-6/CD 6-A. It is essential to understand the distribution and frequency of the relevant mutations in each population where beta-thalassaemias exist. This is of particular importance for genotype-phenotype correlation and for carrier detection, genetic counselling and prenatal diagnosis.
Collapse
Affiliation(s)
- L Rigoli
- Department of Paediatrics, University of Messina, School of Medicine, Italy.
| | | | | | | | | | | | | | | | | |
Collapse
|
47
|
Nadkarni A, Gorakshakar AC, Lu CY, Krishnamoorthy R, Ghosh K, Colah R, Mohanty D. Molecular pathogenesis and clinical variability of beta-thalassemia syndromes among Indians. Am J Hematol 2001; 68:75-80. [PMID: 11559945 DOI: 10.1002/ajh.1156] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Sixty-four homozygous beta-thalassemia patients comprising 40 patients with beta-thalassemia major and 24 patients with beta-thalassemia intermedia were investigated for the nature of their beta-thalassemia mutations, associated alpha-thalassemia, and XmnI polymorphism in the gamma gene which are known to affect the clinical course of the disease. This study was undertaken to look for the contribution of these associated factors in reducing the clinical severity of homozygous beta-thalassemia from a severe disease to a beta-thalassemia intermedia phenotype. Clinical severity of these patients was assessed by the degree of transfusion dependency and the age at which the patient presented with symptoms. Globin chain synthetic ratio was taken as the biochemical pointer of severity of the disease. Eleven different beta-thalassemia mutations were encountered among 128 beta-thalassemia chromosomes. It was observed that the nature of the beta-thalassemia mutations was not very different between the beta-thalassemia major and beta-thalassemia intermedia groups in our patients, but co-inheritance of one or more alpha-globin gene deletions (-alpha(3.7)) and the presence of the XmnI polymorphism were associated with lesser severity of the disease in Indians.
Collapse
Affiliation(s)
- A Nadkarni
- Institute of Immunohaematology (ICMR), 13(th) Floor, NMS Building, KEM Hospital Campus, Parel, Mumbai, India
| | | | | | | | | | | | | |
Collapse
|
48
|
Chang YP, Littera R, Garau R, Smith KD, Dover GJ, Iannelli S, Cacace E, Contu L. The role of heterocellular hereditary persistence of fetal haemoglobin in beta(0)-thalassaemia intermedia. Br J Haematol 2001; 114:899-906. [PMID: 11564083 DOI: 10.1046/j.1365-2141.2001.03042.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Beta(0)-thalassaemia intermedia (beta(0)-TI) describes patients who lack beta-globin synthesis yet manifest a non-transfusion-dependent form of beta-thalassaemia. Co-inheritance of alpha-thalassaemia, certain variants of the beta-like globin gene cluster and elevated fetal haemoglobin (HbF) production are all associated with beta(0)-TI. However, the mild phenotypes of many beta(0)-TI patients are unexplained. Genetically determined HbF levels in beta-thalassaemia are difficult to assess because erythrocytes containing HbF (F cells) preferentially survive over erythrocytes without HbF. To evaluate the importance of genetically elevated HbF in beta-thalassaemia, F-cell levels of 19 TI patients' relatives were compared with relatives of transfusion-dependent beta-thalassaemia major patients and those of beta-globin genotype-matched controls. The beta-globin and alpha-globin genotypes, as well as their Ggamma promoter were also examined. Using this approach, in all but one patient the mild phenotype was attributable to either alpha-globin genotype, gamma-globin promoter polymorphism or inherited elevated F-cell levels. The findings of this study establish the F-cell levels required to modify the degree of disease severity significantly and demonstrate that F-cell level is a crucial parameter in the understanding of phenotypic variation in beta-thalassaemia.
Collapse
Affiliation(s)
- Y P Chang
- Division of Medical Genetics, Department of Internal Medical Science, University of Cagliari, Via Is Guadazzonis, 09100 Cagliari, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
49
|
Cappellini MD, Robbiolo L, Bottasso BM, Coppola R, Fiorelli G, Mannucci AP. Venous thromboembolism and hypercoagulability in splenectomized patients with thalassaemia intermedia. Br J Haematol 2000; 111:467-73. [PMID: 11122086 DOI: 10.1046/j.1365-2141.2000.02376.x] [Citation(s) in RCA: 205] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Thromboembolic phenomena have been described in patients with thalassaemia intermedia and major, although there are relatively few epidemiological data on the overall frequency of these complications. To obtain more insight into the risk and mechanism of venous thromboembolism in thalassaemia, the aims of this study were: (i) to establish retrospectively the prevalence of thromboembolic events in a large group of adults with thalassaemia intermedia and major during a follow up period of 10 years; (ii) to measure in subgroups of these patients sensitive markers of activation of coagulation and fibrinolysis enzymes; and (iii) to look for possible procoagulant mechanisms. A high prevalence of thromboembolic events was found, particularly in splenectomized patients with thalassaemia intermedia (29%). These patients had high plasma levels of markers of coagulation and fibrinolysis activation. Furthermore, thalassaemic red cells and erythroid precursors from splenectomized patients with thalassaemia intermedia had an enhanced capacity to generate thrombin. To evaluate the role of splenectomy per se on procoagulant activity, we evaluated the capacity to form thrombin in healthy individuals who had been splenectomized for trauma. They produced the same amount of thrombin as non-splenectomized controls. In conclusion, the results of this study show the existence of a hypercoagulable state in splenectomized patients with thalassaemia intermedia and that their red and erythroid cells are capable of acting as activated platelets in thrombin generation.
Collapse
Affiliation(s)
- M D Cappellini
- Centre for Congenital Anaemias and Angelo Bianchi Bonomi Haemophilia and Thrombosis Centre and Department of Internal Medicine, IRCCS Maggiore Hospital and University of Milan, Italy.
| | | | | | | | | | | |
Collapse
|
50
|
Domenica Cappellini M, Graziadei G, Ciceri L, Comino A, Bianchi P, Porcella A, Fiorelli G. Oral isobutyramide therapy in patients with thalassemia intermedia: results of a phase II open study. Blood Cells Mol Dis 2000; 26:105-11. [PMID: 10772882 DOI: 10.1006/bcmd.2000.0283] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A pilot phase II open study on 12 patients with thalassemia intermedia (7 men, 5 women; age 31 +/- 2.0 years SE) treated with oral isobutyramide, a derivative of butyric acid (150 mg/kg body wt/day), was performed in order to evaluate the effect of this compound in stimulating hemoglobin F (HbF) production. No patient underwent blood transfusion in the 1-year time frame prior to the study. Nine patients were splenectomized. Safety was monitored by clinical and laboratory tests. Efficacy was assessed in terms of the non-alpha/alpha globin chain biosynthetic ratio and the percentage increase of HbF. The study design consisted of a screening phase, a treatment phase of 28 days, and a posttreatment follow-up of 28 days. All patients completed the study. Compliance to treatment was 100%. No drug-related adverse event was recorded. We observed little or no increase in the non-alpha/alpha ratio in the majority of patients. Six patients showed a percentage increase of HbF at the end of treatment and in 5 of those 6 further increases at the end of the follow-up period were observed. The change in percentage of HbF over time was close to significance both in the treatment period (P = 0. 06) and in the follow-up period (P = 0.08). These results indicate that butyrate derivatives can stimulate fetal hemoglobin in patients with intermediate thalassemia. Testing of the effects of different schedules of administration of isobutyramide will be required in order to determine the optimal use of this compound in the treatment of the beta-thalassemia syndromes.
Collapse
Affiliation(s)
- M Domenica Cappellini
- Centro Anemie Congenite, Università di Milano, Ospedale Maggiore Policlinico IRCCS, Milano, Italy.
| | | | | | | | | | | | | |
Collapse
|