1
|
Hamzah R, Mohamad AS, Mohd Yasin N, Esa E, Chen G, Selvaratnam V. The Characteristics of Compound Heterozygosity for Hemoglobin G-Makassar with Hb E in Malaysia. J Blood Med 2024; 15:255-264. [PMID: 38828362 PMCID: PMC11144427 DOI: 10.2147/jbm.s432849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2023] [Accepted: 03/16/2024] [Indexed: 06/05/2024] Open
Abstract
Background Human hemoglobin of G-Makassar and hemoglobin E (Hb E) are hemoglobin variants that affect Beta (β) globin. Hb G-Makassar is a very rare variant while Hb E is estimated to affect at least one million people worldwide. Both Hb G-Makassar and Hb E can be inherited in the heterozygous, homozygous or compound heterozygous state. This case series describes the characteristics of four individuals with compound heterozygosity for Hb G-Makassar/Hb E cases in Malaysia. To the best of our knowledge, these are the only four individuals with this genotype reported in the literature. Case Series We present four cases of compound heterozygosity for Hb G-Makassar/Hb E identified from October 2014 to January 2021. All the cases were incidental findings whereby the screening Hb analysis showed the presence of peaks in both Hb S and Hb E zones on capillary electrophoresis (CE) and cation-exchange high-performance liquid chromatography (HPLC). Molecular analysis confirmed the findings of compound heterozygous Hb G-Makassar/Hb E. Two cases had a history of anemia secondary to unrelated conditions that resolved with treatment of the underlying cause. The other two cases were asymptomatic individuals who were detected through Malaysia's National Thalassemia Screening program. On the last follow-up, all the individuals were well, non-transfusion dependent, and had no reported history of chronic anemia, bleeding, hemolysis or thromboembolism complications. Conclusion The cases reported here highlight the possibilities for rare compound heterozygous states in multi-ethnicity populations such as Malaysia. Compound heterozygous Hb G-Makassar/Hb E individuals are clinically silent with laboratory values suggesting microcytic and hypochromic red blood cells. Further local epidemiology or population studies with genotyping tests are required for a better understanding of the diversity of its clinical phenotype.
Collapse
Affiliation(s)
- Roszymah Hamzah
- Hematology Department, Ampang Hospital, Ampang, Selangor, Malaysia
| | - Ahmad Sabry Mohamad
- Medical Engineering, Universiti Kuala Lumpur-British Malaysian Institute, Gombak, Selangor, Malaysia
| | - Norafiza Mohd Yasin
- Institute for Medical Research, Ministry of Health, Shah Alam, Selangor, Malaysia
| | - Ezalia Esa
- Institute for Medical Research, Ministry of Health, Shah Alam, Selangor, Malaysia
| | - Guo Chen
- Beam Therapeutics Inc., Cambridge, MA, USA
| | | |
Collapse
|
2
|
Esa E, Mohamad AS, Hamzah R, Hamid FSA, Aziz NA, Sevaratnam V, Sathar J, Chen G, Yasin NM. Clinical and haematological characteristics of 38 individuals with Hb G-Makassar in Malaysia. EJHAEM 2023; 4:940-948. [PMID: 38024609 PMCID: PMC10660101 DOI: 10.1002/jha2.750] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 06/02/2023] [Accepted: 06/20/2023] [Indexed: 12/01/2023]
Abstract
Haemoglobin (Hb) G-Makassar is a rare Hb variant. It presents a diagnostic challenge as it imitates sickle Hb (Hb S) in standard electrophoresis and high-performance liquid chromatography assays requiring DNA analysis to confirm diagnosis. Both have point mutations in codon 6, exon 1 in the β-globin (HBB) gene with different pathogenicities. This study describes the clinical phenotype, haematology and genotype of Hb G-Makassar. Clinical and laboratory data of 38 cases of Hb G-Makassar over 8 years were analysed. Hb G-Makassar was confirmed by a direct sequencing of HBB gene and co-inheritance of α-thalassaemia determined through multiplex gap-PCR and multiplex Amplification Refractory Mutation System polymerase chain reaction. All cases were Malays, predominantly from Terengganu (n = 20, 52.6%). There were 14 (36.8%) males and 24 (63.2%) females with median age of 25 years. Majority (n = 33, 86.8%) had features of thalassaemia trait with mean ± SD for Hb, mean cell volume (MCV) and mean cell haemoglobin (MCH) as 13.21 g/dL ± 1.69, 73.06 ± 4.48 fL and 24.71 ± 1.82 pg, respectively. None had evidence of haemolysis or thromboembolic complications. Six genotypes were identified; ßG-Makassar/ß,αα/αα (n = 19, 50.0%), ßG-Makassar/ßE,αα/αα (n = 4, 10.5%), ßG-Makassar/ßNewYork,αα/αα (n = 1, 2.6%), ßG-Makassar/ß,αα/-α (n = 11, 28.9%), ßG-Makassar/ß,αα/αAdanaα (n = 2, 5.3%) and ßG-Makassar/ß,αα/-SEA (n = 1, 2.6%). The ßG-Makassar/ß,αα/αα showed that features of thalassaemia trait with mean ± SD for Hb, MCV and MCH were 13.74 g/dL ± 2.40, 76.18 ± 6.02 fL and 25.79 ± 2.41 pg, respectively. This is the largest study reporting a significant number of Hb G-Makassar in Malaysia. Although the mutation is similar to Hb S, the phenotype is benign.
Collapse
Affiliation(s)
- Ezalia Esa
- Institute for Medical ResearchSetia AlamSelangorMalaysia
| | - Ahmad Sabry Mohamad
- Medical EngineeringUniversiti Kuala Lumpur British Malaysian InstituteGombakSelangorMalaysia
| | | | | | | | | | - Jameela Sathar
- Hematology DepartmentAmpang HospitalAmpangSelangorMalaysia
| | - Guo Chen
- Beam Therapeutics Inc.CambridgeMassachusettsUSA
| | | |
Collapse
|
3
|
Hardouin G, Magrin E, Corsia A, Cavazzana M, Miccio A, Semeraro M. Sickle Cell Disease: From Genetics to Curative Approaches. Annu Rev Genomics Hum Genet 2023; 24:255-275. [PMID: 37624668 DOI: 10.1146/annurev-genom-120122-081037] [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] [Indexed: 08/27/2023]
Abstract
Sickle cell disease (SCD) is a monogenic blood disease caused by a point mutation in the gene coding for β-globin. The abnormal hemoglobin [sickle hemoglobin (HbS)] polymerizes under low-oxygen conditions and causes red blood cells to sickle. The clinical presentation varies from very severe (with acute pain, chronic pain, and early mortality) to normal (few complications and a normal life span). The variability of SCD might be due (in part) to various genetic modulators. First, we review the main genetic factors, polymorphisms, and modifier genes that influence the expression of globin or otherwise modulate the severity of SCD. Considering SCD as a complex, multifactorial disorder is important for the development of appropriate pharmacological and genetic treatments. Second, we review the characteristics, advantages, and disadvantages of the latest advances in gene therapy for SCD, from lentiviral-vector-based approaches to gene-editing strategies.
Collapse
Affiliation(s)
- Giulia Hardouin
- Laboratory of Chromatin and Gene Regulation During Development, Imagine Institute, INSERM UMR 1163, Université Paris Cité, Paris, France; ,
- Centre d'Investigation Clinique Spécialisé en Biothérapie, Département de Biothérapie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France; ,
- Human Lymphohematopoiesis Laboratory, Imagine Institute, INSERM UMR 1163, Université Paris Cité, Paris, France;
| | - Elisa Magrin
- Centre d'Investigation Clinique Spécialisé en Biothérapie, Département de Biothérapie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France; ,
| | - Alice Corsia
- Human Lymphohematopoiesis Laboratory, Imagine Institute, INSERM UMR 1163, Université Paris Cité, Paris, France;
| | - Marina Cavazzana
- Centre d'Investigation Clinique Spécialisé en Biothérapie, Département de Biothérapie, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France; ,
- Imagine Institute, INSERM UMR 1163, Université Paris Cité, Paris, France
- Université Paris Cité, Paris, France
| | - Annarita Miccio
- Laboratory of Chromatin and Gene Regulation During Development, Imagine Institute, INSERM UMR 1163, Université Paris Cité, Paris, France; ,
| | - Michaela Semeraro
- Université Paris Cité, Paris, France
- Centre d'Investigation Clinique and Unité de Recherche Clinique, Hôpital Necker-Enfants Malades, Assistance Publique-Hôpitaux de Paris, Paris, France;
| |
Collapse
|
4
|
Maity D, Pal D. Molecular Dynamics of Hemoglobin Reveals Structural Alterations and Explains the Interactions Driving Sickle Cell Fibrillation. J Phys Chem B 2021; 125:9921-9933. [PMID: 34459602 DOI: 10.1021/acs.jpcb.1c01684] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In sickle cell anemia, deoxyhemoglobin deforms RBCs by forming fibrils inside that disintegrate on oxygenation. We studied 100 ns long all-atom molecular dynamics (MD) for sickle and normal hemoglobin fibril models to understand this process, complemented by multiple 1 μs MD for a single tetramer of sickle and normal hemoglobin in deoxy and oxy states. We find that the presence of hydrophobic residues without a bulky side chain at β-6 in hemoglobin is the reason for the stability of the fibrils. Moreover, the free energy landscapes from MD of hemoglobin starting in the tensed (T) state capture the putative transition from T to relaxed (R) state, associated with oxygen binding. The three conformational wells in the landscapes are characterized by the quaternary changes where one αβ dimer rotates with respect to the other. The conformational changes from the oxygenation of sickle hemoglobin hinder the intermolecular contacts necessary for fibril formation.
Collapse
Affiliation(s)
- Dibyajyoti Maity
- Department of Computational and Data Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India
| | - Debnath Pal
- Department of Computational and Data Sciences, Indian Institute of Science, Bangalore 560012, Karnataka, India
| |
Collapse
|
5
|
Doerfler PA, Sharma A, Porter JS, Zheng Y, Tisdale JF, Weiss MJ. Genetic therapies for the first molecular disease. J Clin Invest 2021; 131:146394. [PMID: 33855970 PMCID: PMC8262557 DOI: 10.1172/jci146394] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Sickle cell disease (SCD) is a monogenic disorder characterized by recurrent episodes of severe bone pain, multi-organ failure, and early mortality. Although medical progress over the past several decades has improved clinical outcomes and offered cures for many affected individuals living in high-income countries, most SCD patients still experience substantial morbidity and premature death. Emerging technologies to manipulate somatic cell genomes and insights into the mechanisms of developmental globin gene regulation are generating potentially transformative approaches to cure SCD by autologous hematopoietic stem cell (HSC) transplantation. Key components of current approaches include ethical informed consent, isolation of patient HSCs, in vitro genetic modification of HSCs to correct the SCD mutation or circumvent its damaging effects, and reinfusion of the modified HSCs following myelotoxic bone marrow conditioning. Successful integration of these components into effective therapies requires interdisciplinary collaborations between laboratory researchers, clinical caregivers, and patients. Here we summarize current knowledge and research challenges for each key component, emphasizing that the best approaches have yet to be developed.
Collapse
Affiliation(s)
| | - Akshay Sharma
- Department of Bone Marrow Transplantation and Cellular Therapy
| | | | - Yan Zheng
- Department of Pathology, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA
| | - John F. Tisdale
- Cellular and Molecular Therapeutics Branch, National Heart, Lung, and Blood Institute, NIH, Bethesda, Maryland, USA
| | | |
Collapse
|
6
|
Chu SH, Packer M, Rees H, Lam D, Yu Y, Marshall J, Cheng LI, Lam D, Olins J, Ran FA, Liquori A, Gantzer B, Decker J, Born D, Barrera L, Hartigan A, Gaudelli N, Ciaramella G, Slaymaker IM. Rationally Designed Base Editors for Precise Editing of the Sickle Cell Disease Mutation. CRISPR J 2021; 4:169-177. [PMID: 33876959 DOI: 10.1089/crispr.2020.0144] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Base editors are fusions of a deaminase and CRISPR-Cas ribonucleoprotein that allow programmable installment of transition mutations without double-strand DNA break intermediates. The breadth of potential base editing targets is frequently limited by the requirement of a suitably positioned Cas9 protospacer adjacent motif. To address this, we used structures of Cas9 and TadA to design a set of inlaid base editors (IBEs), in which deaminase domains are internal to Cas9. Several of these IBEs exhibit shifted editing windows and greater editing efficiency, enabling editing of targets outside the canonical editing window with reduced DNA and RNA off-target editing frequency. Finally, we show that IBEs enable conversion of the pathogenic sickle cell hemoglobin allele to the naturally occurring HbG-Makassar variant in patient-derived hematopoietic stem cells.
Collapse
Affiliation(s)
| | | | | | | | - Yi Yu
- Beam Therapeutics, Cambridge, MA, USA
| | | | | | - Daisy Lam
- Beam Therapeutics, Cambridge, MA, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
7
|
Brusson M, Miccio A. Genome editing approaches to β-hemoglobinopathies. PROGRESS IN MOLECULAR BIOLOGY AND TRANSLATIONAL SCIENCE 2021; 182:153-183. [PMID: 34175041 DOI: 10.1016/bs.pmbts.2021.01.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
β-hemoglobinopathies are the most common monogenic disorders worldwide and are caused by mutations in the β-globin locus altering the production of adult hemoglobin (HbA). Transplantation of autologous hematopoietic stem cells (HSCs) corrected by lentiviral vector-mediated addition of a functional β-like globin raised new hopes to treat sickle cell disease and β-thalassemia patients; however, the low expression of the therapeutic gene per vector copy is often not sufficient to fully correct the patients with a severe clinical phenotype. Recent advances in the genome editing field brought new possibilities to cure β-hemoglobinopathies by allowing the direct modification of specific endogenous loci. Double-strand breaks (DSBs)-inducing nucleases (i.e., ZFNs, TALENs and CRISPR-Cas9) or DSB-free tools (i.e., base and prime editing) have been used to directly correct the disease-causing mutations, restoring HbA expression, or to reactivate the expression of the fetal hemoglobin (HbF), which is known to alleviate clinical symptoms of β-hemoglobinopathy patients. Here, we describe the different genome editing tools, their application to develop therapeutic approaches to β-hemoglobinopathies and ongoing clinical trials using genome editing strategies.
Collapse
Affiliation(s)
- Mégane Brusson
- Université de Paris, Imagine Institute, Laboratory of Chromatin and Gene Regulation During Development, INSERM UMR 1163, Paris, France.
| | - Annarita Miccio
- Université de Paris, Imagine Institute, Laboratory of Chromatin and Gene Regulation During Development, INSERM UMR 1163, Paris, France.
| |
Collapse
|
8
|
Frati G, Miccio A. Genome Editing for β-Hemoglobinopathies: Advances and Challenges. J Clin Med 2021; 10:482. [PMID: 33525591 PMCID: PMC7865242 DOI: 10.3390/jcm10030482] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2020] [Revised: 01/19/2021] [Accepted: 01/25/2021] [Indexed: 02/08/2023] Open
Abstract
β-hemoglobinopathies are the most common genetic disorders worldwide and are caused by mutations affecting the production or the structure of adult hemoglobin. Patients affected by these diseases suffer from anemia, impaired oxygen delivery to tissues, and multi-organ damage. In the absence of a compatible donor for allogeneic bone marrow transplantation, the lifelong therapeutic options are symptomatic care, red blood cell transfusions and pharmacological treatments. The last decades of research established lentiviral-mediated gene therapy as an efficacious therapeutic strategy. However, this approach is highly expensive and associated with a variable outcome depending on the effectiveness of the viral vector and the quality of the cell product. In the last years, genome editing emerged as a valuable tool for the development of curative strategies for β-hemoglobinopathies. Moreover, due to the wide range of its applications, genome editing has been extensively used to study regulatory mechanisms underlying globin gene regulation allowing the identification of novel genetic and pharmacological targets. In this work, we review the current advances and challenges of genome editing approaches to β-hemoglobinopathies. Special focus has been directed towards strategies aimed at correcting the defective β-globin gene or at inducing fetal hemoglobin (HbF), which are in an advanced state of clinical development.
Collapse
Affiliation(s)
- Giacomo Frati
- Laboratory of Chromatin and Gene Regulation during Development, Imagine Institute, Université de Paris, INSERM UMR 1163, F-75015 Paris, France
| | - Annarita Miccio
- Laboratory of Chromatin and Gene Regulation during Development, Imagine Institute, Université de Paris, INSERM UMR 1163, F-75015 Paris, France
| |
Collapse
|
9
|
Antoniou P, Miccio A, Brusson M. Base and Prime Editing Technologies for Blood Disorders. Front Genome Ed 2021; 3:618406. [PMID: 34713251 PMCID: PMC8525391 DOI: 10.3389/fgeed.2021.618406] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/04/2021] [Indexed: 12/14/2022] Open
Abstract
Nuclease-based genome editing strategies hold great promise for the treatment of blood disorders. However, a major drawback of these approaches is the generation of potentially harmful double strand breaks (DSBs). Base editing is a CRISPR-Cas9-based genome editing technology that allows the introduction of point mutations in the DNA without generating DSBs. Two major classes of base editors have been developed: cytidine base editors or CBEs allowing C>T conversions and adenine base editors or ABEs allowing A>G conversions. The scope of base editing tools has been extensively broadened, allowing higher efficiency, specificity, accessibility to previously inaccessible genetic loci and multiplexing, while maintaining a low rate of Insertions and Deletions (InDels). Base editing is a promising therapeutic strategy for genetic diseases caused by point mutations, such as many blood disorders and might be more effective than approaches based on homology-directed repair, which is moderately efficient in hematopoietic stem cells, the target cell population of many gene therapy approaches. In this review, we describe the development and evolution of the base editing system and its potential to correct blood disorders. We also discuss challenges of base editing approaches-including the delivery of base editors and the off-target events-and the advantages and disadvantages of base editing compared to classical genome editing strategies. Finally, we summarize the recent technologies that have further expanded the potential to correct genetic mutations, such as the novel base editing system allowing base transversions and the more versatile prime editing strategy.
Collapse
Affiliation(s)
| | - Annarita Miccio
- Université de Paris, Imagine Institute, Laboratory of Chromatin and Gene Regulation During Development, INSERM UMR 1163, Paris, France
| | - Mégane Brusson
- Université de Paris, Imagine Institute, Laboratory of Chromatin and Gene Regulation During Development, INSERM UMR 1163, Paris, France
| |
Collapse
|