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Singha K, Tepakhan W, Yamsri S, Chaibunruang A, Srivorakun H, Pansuwan A, Fucharoen G, Fucharoen S. A large cohort of Hb H disease in northeast Thailand: A molecular revisited, diverse genetic interactions and identification of a novel mutation. Clin Chim Acta 2024; 561:119830. [PMID: 38914363 DOI: 10.1016/j.cca.2024.119830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/21/2024] [Accepted: 06/22/2024] [Indexed: 06/26/2024]
Abstract
BACKGROUND AND AIMS To update the molecular characteristics of α-thalassemia in northeast Thailand, the molecular basis and genetic interactions of Hb H disease were examined in a large cohort of patients. MATERIALS AND METHODS A study was done on 1,170 subjects with Hb H disease and various genetic interactions encountered during 2009-2023. Hb and DNA analyses were carried out. RESULTS As many as 40 genotypes with several known, previously undescribed, and novel mutations were observed. These included 698 subjects (59.8 %) of Hb H disease, 357 (30.6 %) with EABart's disease, 63 (5.4 %) with EEBart's disease, 18 (1.7 %) with abnormal Hbs, 17 (1.5 %) with β-thalassemia, and 4 (0.4 %) with EFBart's or EFABart's disease. The molecular basis of 13 subjects (1.1 %) remains unknown. The α0-thalassemia included --SEA (n = 1,139, 97.4 %) and --THAI (n = 21, 1.8 %). Two rare mutations were identified in 3 subjects (0.3 %) with --SA and --CR deletions. For α+-thalassemia, -α3.7 kb del (n = 626, 53.5 %), Hb Constant Spring (n = 415, 35.5 %), -α4.2 kb del (n = 44, 3.8 %), Hb Paksé (n = 36, 3.1 %), and Hb Q-Thailand (n = 19, 1.6 %), were detected. Ten rarer α+-thalassemia were identified, including a novel mutation, namely the Hb Chumphae (HBA2:c.32T>A). The Hb H-Lansing-Ramathibodi, Hb H-Jax, and Hb H-Chumphae are hitherto undescribed in this region. PCR-based diagnostic methods for these α-thalassemia defects were described. CONCLUSIONS This study confirms the diverse heterogeneity and genetic interactions causing Hb H disease in northeast Thailand. The results should prove useful for laboratory diagnosis and genetic counseling of this genetic disorder in the region.
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Affiliation(s)
- Kritsada Singha
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand; Faculty of Medicine, Mahasarakham University, Mahasarakham, Thailand
| | - Wanicha Tepakhan
- Department of Pathology, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Supawadee Yamsri
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Attawut Chaibunruang
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Hataichanok Srivorakun
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Anupong Pansuwan
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Goonnapa Fucharoen
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Supan Fucharoen
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
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mRNA Analysis of Frameshift Mutations with Stop Codon in the Last Exon: The Case of Hemoglobins Campania [α1 cod95 (-C)] and Sciacca [α1 cod109 (-C)]. Biomedicines 2021; 9:biomedicines9101390. [PMID: 34680508 PMCID: PMC8533187 DOI: 10.3390/biomedicines9101390] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Revised: 09/27/2021] [Accepted: 09/29/2021] [Indexed: 12/05/2022] Open
Abstract
An insertion or deletion of a nucleotide (nt) in the penultimate or the last exon can result in a frameshift and premature termination codon (PTC), giving rise to an unstable protein variant, showing a dominant phenotype. We described two α-globin mutants created by the deletion of a nucleotide in the penultimate or the last exon of the α1-globin gene: the Hb Campania or α1 cod95 (−C), causing a frameshift resulting in a PTC at codon 102, and the Hb Sciacca or α1 cod109 (−C), causing a frameshift and formation of a PTC at codon 133. The carriers showed α-thalassemia alterations (mild microcytosis with normal Hb A2) and lacked hemoglobin variants. The 3D model indicated the α-chain variants’ instability, due to the severe structural alterations with impairment of the chaperone alpha-hemoglobin stabilizing protein (AHSP) interaction. The qualitative and semiquantitative analyses of the α1mRNA from the reticulocytes of carriers highlighted a reduction in the variant cDNAs that constituted 34% (Hb Campania) and 15% (Hb Sciacca) of the total α1-globin cDNA, respectively. We developed a workflow for the in silico analysis of mechanisms triggering no-go decay, and its results suggested that the reduction in the variant mRNA was likely due to no-go decay caused by the presence of a rare triplet, and, in the case of Hb Sciacca, also by the mRNA’s secondary structure variation. It would be interesting to correlate the phenotype with the quantity of other frameshift mRNA variants, but very few data concerning α- and β-globin variants are available.
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Yin Z, Hao Y, Huang X, Chen X, Chen S, Li G, Chen C, Wei F. A Novel Mutation at HBA1: c.349G>T Causing α-Thalassemia in a Chinese Family. Hemoglobin 2021; 45:94-96. [PMID: 34082638 DOI: 10.1080/03630269.2021.1925292] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
α-Thalassemia (α-thal) is one of the most common genetic diseases in Southern China. Although more than 300 α-thal mutations have been reported in the world, the mutation spectrum is still not comprehensive. In this study, a novel mutation (HBA1: c.349G>T) in a newborn (proband) was first found by next-generation sequencing (NGS). Subsequently, hematological analysis and thalassemia genetic testing were performed for the family members. The results showed that both the proband and her mother were heterozygotes for this novel mutation and presented abnormal hematological indices. Based on the features observed in clinical practice, this novel mutation was considered as a type of α-thal variation.
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Affiliation(s)
- Zhenzhen Yin
- Nanfang College, Guangzhou, Guangdong Province, China
| | - Yuqi Hao
- Anhui Jinzhai Technical College (Anhui Jinzhai Vocational School), Liuan, Anhui Province, China
| | - Xiaoyan Huang
- Clinical Laboratory of BGI Health, BGI-Shenzhen, Shenzhen, Guandong Province, China
| | - Xiaohang Chen
- The Genetics Laboratory, Shenzhen Longgang District Maternity and Child Healthcare Hospital, Shenzhen, Guandong Province, China
| | - Shiping Chen
- Clinical Laboratory of BGI Health, BGI-Shenzhen, Shenzhen, Guandong Province, China
| | - Gaochi Li
- The Genetics Laboratory, Shenzhen Longgang District Maternity and Child Healthcare Hospital, Shenzhen, Guandong Province, China
| | - Chuyan Chen
- Nanfang College, Guangzhou, Guangdong Province, China
| | - Fengxiang Wei
- The Genetics Laboratory, Shenzhen Longgang District Maternity and Child Healthcare Hospital, Shenzhen, Guandong Province, China
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Panyasai S, Phasit A. α-Thalassemia Intermedia Results from Interactions of Unstable Hb Prato [α31(B12)Arg→Ser ( HBA1 or HBA2 c.96G>T or C)] with the α-Thalassemia-1 [- - SEA (Southeast Asian)] Deletion in Thailand. Hemoglobin 2020; 44:264-271. [PMID: 32727229 DOI: 10.1080/03630269.2020.1797773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
The clinical consequences of many abnormal hemoglobins (Hbs) interacting with α- or β-thalassemia (α- or β-thal) or other hemoglobinopathies have not been described. We evaluated a 75-year-old Thai woman and her 45-year-old daughter. Hematological data was obtained on an automated cell counter. Hemoglobin (Hb) analysis was carried out using high performance liquid chromatography (HPLC) and capillary electrophoresis (CE) assays. Mutations and globin haplotypes were identified by appropriated DNA techniques. The proband presented with moderate anemia and inclusion bodies in most of the red blood cells (RBCs), while altered RBC parameters were absent in her daughter. Hemoglobin analysis showed an abnormal Hb peak only in the proband. DNA analysis identified a G>T substitution at codon 31 of the α1-globin gene, corresponding to Hb Prato [α31(B12)Arg→Ser (HBA1 or HBA2 c.96G>T or C)] in both subjects. The α-thal-1 [- -SEA (Southeast Asian)] deletion was also identified in the proband, but not in her daughter. These mutations could be identified using newly developed allele-specific polymerase chain reaction (ASPCR) assays. The α haplotypic analysis demonstrated the Thai Hb Prato allele was associated with haplotype [+ - S + - + -] [the S represents the inter ζ hypervariable region (HVR)]. The combination of the unstable Hb Prato with α-thal-1 result in α-thal intermedia (α-TI) phenotypes. A simple DNA method is essential for detection, and a haplotypic α-globin gene cluster are presented.
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Affiliation(s)
- Sitthichai Panyasai
- Department of Medical Technology, School of Allied Health Sciences, University of Phayao, Phayao, Thailand
| | - Amphai Phasit
- Department of Medical Technology, Lampang Hospital, Lampang, Thailand
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Singha K, Wiangnon S, Fucharoen G, Jetsrisuparb A, Komwilaisak P, Fucharoen S. Severe thalassemia syndrome caused by Hemoglobin Pak Num Po AEBart's disease: A hematological, molecular, and diagnostic aspects. Int J Lab Hematol 2020; 42:e173-e176. [PMID: 32359030 DOI: 10.1111/ijlh.13224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2020] [Revised: 04/06/2020] [Accepted: 04/11/2020] [Indexed: 12/01/2022]
Affiliation(s)
- Kritsada Singha
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Surapon Wiangnon
- Faculty of Medicine, Mahasarakham University, Mahasarakham, Thailand
| | - Goonnapa Fucharoen
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
| | - Arunee Jetsrisuparb
- Department of Pediatrics, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Patcharee Komwilaisak
- Department of Pediatrics, Faculty of Medicine, Khon Kaen University, Khon Kaen, Thailand
| | - Supan Fucharoen
- Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand
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Jiang H, Huang LY, Zhen L, Jiang F, Li DZ. Two α1-Globin Gene Point Mutations Causing Severe Hb H Disease. Hemoglobin 2017; 41:293-296. [DOI: 10.1080/03630269.2017.1390478] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Affiliation(s)
- Hua Jiang
- Department of Hematology/Oncology, Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Lv-Yin Huang
- Prenatal Diagnostic Center, Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Li Zhen
- Prenatal Diagnostic Center, Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Fan Jiang
- Prenatal Diagnostic Center, Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Dong-Zhi Li
- Prenatal Diagnostic Center, Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
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Farashi S, Najmabadi H. Diagnostic pitfalls of less well recognized HbH disease. Blood Cells Mol Dis 2015; 55:387-95. [DOI: 10.1016/j.bcmd.2015.08.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Revised: 08/06/2015] [Accepted: 08/06/2015] [Indexed: 10/23/2022]
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Farashi S, Faramarzi Garous N, Ashki M, Vakili S, Zeinali F, Imanian H, Azarkeivan A, Najmabadi H. Hb Dartmouth (HBA2: c.200T>C): An α2-Globin Gene Associated with Hb H Disease in One Homozygous Patient. Hemoglobin 2015; 39:152-5. [DOI: 10.3109/03630269.2015.1027915] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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Taweevisit M, Thorner PS. The contribution of extramedullary hematopoiesis to hepatomegaly in anemic hydrops fetalis: a study in alpha-thalassemia hydrops fetalis. Pediatr Dev Pathol 2012; 15:206-12. [PMID: 22369064 DOI: 10.2350/11-12-1126-oa.1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Massive hepatomegaly is a common finding in hydrops fetalis (HF) arising from hemoglobinopathies. It has been suggested that extramedullary hematopoiesis, which is markedly increased in response to anemia, plays a principal role in hepatomegaly via sinusoidal obstruction and distortion of the intrahepatic architecture. To test this concept, the authors compared 20 cases of α-thalassemia (hemoglobin Bart, 15 cases; hemoglobin H, 5 cases) with 19 cases of HF arising from other causes and 39 control nonhydrops cases. The mean liver weight in α-thalassemia cases was significantly heavier than in control cases and in hydrops fetalis cases due to other causes (P < 0.01). This was not explainable on the basis of extramedullary hematopoiesis (erythropoiesis or myelopoiesis) or hemosiderin deposition, since cases of HF from other causes, especially related to anemia, showed similar findings to α-thalassemia cases. While these processes no doubt contribute to hepatic weight, the major factor would still be high-output cardiac failure causing hepatic congestion.
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Affiliation(s)
- Mana Taweevisit
- Department of Pathology, Chulalongkorn University, Bangkok, Thailand.
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Sroymora S, Jindadamrongwech S, Butthep P, Chuncharunee S. Nondeletional Hb Queens Park [α32(B13)Met→Lys]/Hb H (β4) disease. Hemoglobin 2012; 36:293-8. [PMID: 22384838 DOI: 10.3109/03630269.2012.658939] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
A rare nondeletional α-thalassemia-2 (α-thal-2) allele was identified in a Thai boy with Hb H (β4) disease. The proband has α-thal-1 (- -(SEA) type) together with a non productive Hb Queens Park (HBA1:c.98T>A) [α32(B13)Met→Lys] α1-globin variant. No abnormal hemoglobin (Hb) fraction was detected by high performance liquid chromatography (HPLC). The clinical effect of this mutation in the proband was comparable to that of deletional α-thal-2 present in Hb H disease.
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Affiliation(s)
- Suravee Sroymora
- Blood Disease Diagnostic Center, Hematology Division, Department of Pathology, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Rama 6 Road, Bangkok, Thailand
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Haywood A, Dreau H, Timbs A, Schuh A, Old J, Henderson S. Screening for clinically significant non-deletional alpha thalassaemia mutations by pyrosequencing. Ann Hematol 2010; 89:1215-21. [PMID: 20567827 DOI: 10.1007/s00277-010-1013-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Accepted: 06/08/2010] [Indexed: 11/29/2022]
Abstract
Non-deletional α(+)-thalassaemia is associated with a higher degree of morbidity and mortality than deletional forms of α(+)-thalassaemia. Screening for the common deletional forms of α-thalassaemia by Gap-PCR is widely practiced; however, the detection of non-deletional α-thalassaemia mutations is technically more labour-intensive and expensive, as it requires DNA sequencing. In addition, the presence of four very closely homologous alpha globin genes and the frequent co-existence of deletional forms of α-thalassaemia present another layer of complexity in the detection of these mutations. With growing evidence that non-deletional α-thalassaemia is relatively common in the UK, there is a demand for technologies which can quickly and accurately screen for these mutations. We describe a method utilising pyrosequencing for detecting the ten most common clinically significant non-deletional α-thalassaemia mutations in the UK. We tested 105 patients with non-deletional α-thalassaemia and found 100% concordance with known genotype as identified by Sanger sequencing. We found pyrosequencing to be simpler, more robust, quicker, and cheaper than conventional sequencing, making it a good choice for rapid and cost-effective diagnosis of patients with suspected non-deletional α-thalassaemia. The technique is also likely to help expedite prenatal diagnosis of pregnancies at risk of α-thalassaemia major.
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Affiliation(s)
- Anna Haywood
- National Haemoglobinopathy Reference Laboratory, Molecular Haematology, Haemophilia Centre, Churchill Hospital, Oxford Radcliffe NHS Trust, Oxford, UK OX3 7LJ.
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Abstract
Alpha-thalassaemia mutations are common. In Southeast Asia, they cause Hb H disease and Hb Barts hydrops fetalis. Fetuses with the devastating Hb Barts hydrops fetalis due to the complete lack of alpha-globin gene die in utero or shortly after birth, often during the second or third trimesters. Recent findings on patients with Hb H disease who have only one active alpha-globin gene suggest that it is not necessarily a benign disorder as previously thought. The disease burden of these syndromes and their public health importance have been largely neglected. We review the population carrier frequencies of alpha-thalassaemia, and summarize the clinical features, diagnostic approaches, counselling and management of these common genetic disorders. Several practical proposals are made that, if implemented, can begin to address the issues of collaboration and improvement for care of these common diseases in the region.
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Affiliation(s)
- David H K Chui
- Department of Medicine, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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Eng B, Patterson M, Walker L, Hoppe C, Azimi M, Lee H, Giordano PC, Waye JS. Three New α-Thalassemia Point Mutations Ascertained Through Newborn Screening. Hemoglobin 2009; 30:149-53. [PMID: 16798638 DOI: 10.1080/03630260600642021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
We report three new alpha-thalassemia (thal) point mutations detected during newborn screening for hemoglobinopathies. The first mutation is a single nucleotide deletion (-A) that abolishes the translation initiation codon of the alpha2-globin gene, detected in a newborn of Hmong ethnicity who carried the Southeast Asian alpha(0)-thal deletion (alpha(T)alpha/- -(SEA)). The second mutation, a frameshift caused by a single nucleotide deletion in exon 2 of the alpha1-globin gene [codon 78 (-C)], was detected in a Black/Chinese newborn who also carried the Southeast Asian alpha0-thal deletion (alphaalpha(T)/- -(SEA)). The third mutation was a frameshift in exon 3 of the alpha2-globin gene, codons 113/114 (-C). This mutation was detected in a newborn who carried the 3.7 kb alpha(+)-thal deletion (alpha(T)alpha/-alpha(3.7)).
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Affiliation(s)
- Barry Eng
- Hamilton Regional Laboratory Medicine Program, Hamilton Health Sciences, Ontario, Canada
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Wajcman H, Traeger-Synodinos J, Papassotiriou I, Giordano PC, Harteveld CL, Baudin-Creuza V, Old J. Unstable and Thalassemic α Chain Hemoglobin Variants: A Cause of Hb H Disease and Thalassemia Intermedia. Hemoglobin 2009; 32:327-49. [DOI: 10.1080/03630260802173833] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Joly P, Pégourié B, Courby S, Barro C, Besson G, Cohen L, Garcia C, Francina A. Two New α-Thalassemia Point Mutations that are Undetectable by Biochemical Techniques. Hemoglobin 2009; 32:411-7. [DOI: 10.1080/03630260802173791] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
Abstract
Hemoglobin H (Hb H) disease is the most common form of thalassemia intermedia and has many features that require careful consideration in management. In the majority of cases, Hb H disease results from double heterozygosity for α0-thalassemia due to deletions that remove both linked α-globin genes on chromosome 16, and deletional α+-thalassemia from single α-globin gene deletions (--/−α). However, Hb H disease may occur from interactions between α0-thalassemia with non-deletional mutations (αTα or αT) or with abnormal hemoglobins such as Hb Constant Spring, Hb Paksé, Hb Quong Sze, and Hb Pak Num Po. In a steady state, patients with Hb H diseases have hemoglobin levels around 9 to 10 g/dL; however, during hemolytic crisis, which frequently develops in or after acute infections with high fever, the hemoglobin level may drop significantly and patients can develop shock or renal shutdown. Even though splenectomy leads to significant elevation of hemoglobin levels, it is not recommended because the majority of patients do well with said steady-state hemoglobin levels. Patients with non-deletional Hb H disease are usually more anemic with significant splenomegaly, and some may require regular blood transfusions and be even as severe as “Hb H hydrops fetalis.” However, there is no clear genotype-phenotype correlation associated with this severe clinical syndrome since patients with identical genotypes do not necessary show the same severity. This suggests that other genetic and environmental factors play a role in modifying the degree of clinical severity in patients with non-deletional Hb H disease.
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Tongsong T, Srisupundit K, Luewan S. Outcomes of pregnancies affected by hemoglobin H disease. Int J Gynaecol Obstet 2008; 104:206-8. [DOI: 10.1016/j.ijgo.2008.10.010] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 09/25/2008] [Accepted: 10/13/2008] [Indexed: 11/29/2022]
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Puehringer H, Najmabadi H, Law HY, Krugluger W, Viprakasit V, Pissard S, Baysal E, Taher A, Farra C, Al-Ali A, Al-Ateeq S, Oberkanins C. Validation of a reverse-hybridization StripAssay for the simultaneous analysis of common α-thalassemia point mutations and deletions. Clin Chem Lab Med 2007; 45:605-10. [PMID: 17484620 DOI: 10.1515/cclm.2007.125] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND alpha-Thalassemia is a worldwide disease and considered to be a major public health problem in countries within the so-called thalassemia belt. The complex genetics of alpha-thalassemias requires diagnostic methods with the capacity to screen rapidly and accurately for common causative mutations. METHODS We developed and validated a reverse-hybridization assay (Alpha-Globin StripAssay) for the rapid and simultaneous detection of 21 alpha-globin mutations: two single gene deletions (-alpha(3.7); -alpha(4.2)), five double gene deletions [--(MED); --(SEA); --(THAI); --(FIL); -(alpha)(20.5)], alpha alpha alpha(anti-3.7) gene triplication, two point mutations in the alpha1 gene (cd 14 G>A; Hb Adana) and 11 point mutations in the alpha2 gene (initiation cd T>C; cd 19 -G; IVS1 -5nt; cd 59 G>A; Hb Quong Sze; Hb Constant Spring; Hb Icaria; Hb Pakse; Hb Koya Dora; polyA-1; polyA-2). RESULTS Reliable genotyping of recombinant mutant clones and reference DNA samples was achieved by means of two corresponding test strips presenting parallel arrays of allele-specific oligonucleotides. The entire procedure from blood sampling to the identification of mutations required less than 6 h, and hybridization/detection was manual or automated. The diagnostic potential of this Alpha-Globin StripAssay was carefully evaluated on 272 pre-typed samples in a multicenter validation study. In 96.14% of the cases, StripAssay typing was completely concordant with the reference methods. CONCLUSIONS The Alpha-Globin StripAssay proved to be a fast, easy-to-perform and reliable screening method to identify >90% of alpha-globin mutations in endemic areas worldwide.
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Abstract
alpha-Thalassemia mutations are one of the most common mutations of man, and they cause Hb H disease and Hb Barts hydrops fetalis. Hb H disease is not necessarily a benign disorder as has been generally thought. Furthermore, in southern China and in Southeast Asia, there are 2-3 times more fetuses afflicted with the invariably fatal Hb Barts hydrops fetalis than with the beta-thalassemia major or intermedia. These findings underscore the public health importance of these hereditary disorders, and they call for better education, diagnosis, treatment, prevention, and research for these diseases.
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Affiliation(s)
- David H K Chui
- Department of Medicine and Pathology, Boston University School of Medicine, 88 East Newton Street, Boston, MA 02118, USA.
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Viprakasit V, Chinchang W, Glomglao W, Tanphaichitr VS. A rare association of alphaO-thalassemia (--SEA) and an initiation codon mutation (ATG-->A-G) of the alpha2 gene causes Hb H disease in Thailand. Hemoglobin 2005; 29:235-40. [PMID: 16116675 DOI: 10.1081/hem-200066339] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Several rare and hitherto unidentified non deletional alpha-thalassemias (alphaTalpha or alphaalphaT) have been reported from Thailand within the past few years. Interactions of these determinants with alphaO-thalassemia (thal) (--/), which is highly prevalent in this region, give rise to various genotypes (--/ alphaTalpha or --/alphaalphaT) underlying Hb H disease. We report herein the interaction of a rare initiation codon mutation of the alpha2 gene and alphaO-thal in a Thai boy with Hb H disease. This finding highlights a wide variety of molecular pathology of the alpha-globin genes underlying alpha-thal syndrome in Southeast Asia.
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Affiliation(s)
- Vip Viprakasit
- Department of Paediatrics, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand.
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