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Harteveld CL, Achour A, Fairuz Mohd Hasan NF, Legebeke J, Arkesteijn SJG, ter Huurne J, Verschuren M, Bhagwandien-Bisoen S, Schaap R, Vijfhuizen L, el Idrissi H, Babbs C, Higgs DR, Koopmann TT, Vrettou C, Traeger-Synodinos J, Baas F. Loss-of-Function Variants in SUPT5H as Modifying Factors in Beta-Thalassemia. Int J Mol Sci 2024; 25:8928. [PMID: 39201615 PMCID: PMC11354595 DOI: 10.3390/ijms25168928] [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: 07/04/2024] [Revised: 08/09/2024] [Accepted: 08/12/2024] [Indexed: 09/02/2024] Open
Abstract
It is well known that modifiers play a role in ameliorating or exacerbating disease phenotypes in patients and carriers of recessively inherited disorders such as sickle cell disease and thalassemia. Here, we give an overview of the literature concerning a recently described association in carriers of SUPT5H Loss-of-Function variants with a beta-thalassemia-like phenotype including the characteristic elevated levels of HbA2. That SUPT5H acts as modifier in beta-thalassemia carriers became evident from three reported cases in whom combined heterozygosity of SUPT5H and HBB gene variants was observed to resemble a mild beta-thalassemia intermedia phenotype. The different SUPT5H variants and hematologic parameters reported are collected and reviewed to provide insight into the possible effects on hematologic expression, as well as potential disease mechanisms in carriers and patients.
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Affiliation(s)
- Cornelis L. Harteveld
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Ahlem Achour
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
- Department of Congenital and Hereditary Diseases, Charles Nicolle Hospital, Tunis 3000, Tunisia
| | - Nik Fatma Fairuz Mohd Hasan
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
- Department of Pathology, Hospital Raja Perempuan Zainab II, Kota Bharu 15400, Malaysia
| | - Jelmer Legebeke
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Sandra J. G. Arkesteijn
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Jeanet ter Huurne
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Maaike Verschuren
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Sharda Bhagwandien-Bisoen
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Rianne Schaap
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Linda Vijfhuizen
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Hakima el Idrissi
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Christian Babbs
- Radcliffe Department of Medicine, Medical Sciences Division, University of Oxford, Oxford OX3 9DU, UK
| | - Douglas R. Higgs
- Radcliffe Department of Medicine, Medical Sciences Division, University of Oxford, Oxford OX3 9DU, UK
| | - Tamara T. Koopmann
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
| | - Christina Vrettou
- Laboratory of Medical Genetics, National and Kapodistrian University of Athens, St. Sophia’s Children’s Hospital, 115 27 Athens, Greece
| | - Joanne Traeger-Synodinos
- Laboratory of Medical Genetics, National and Kapodistrian University of Athens, St. Sophia’s Children’s Hospital, 115 27 Athens, Greece
| | - Frank Baas
- Department of Clinical Genetics/LDGA, Leiden University Medical Center, P.O. Box 9600, 2333 ZC Leiden, The Netherlands
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2
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Huang S, Reed C, Ilsley M, Magor G, Tallack M, Landsberg M, Mitchell H, Gillinder K, Perkins A. Mutations in linker-2 of KLF1 impair expression of membrane transporters and cytoskeletal proteins causing hemolysis. Nat Commun 2024; 15:7019. [PMID: 39147774 PMCID: PMC11327367 DOI: 10.1038/s41467-024-50579-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Accepted: 07/09/2024] [Indexed: 08/17/2024] Open
Abstract
The SP/KLF family of transcription factors harbour three C-terminal C2H2 zinc fingers interspersed by two linkers which confers DNA-binding to a 9-10 bp motif. Mutations in KLF1, the founding member of the family, are common. Missense mutations in linker two result in a mild phenotype. However, when co-inherited with loss-of-function mutations, they result in severe non-spherocytic hemolytic anemia. We generate a mouse model of this disease by crossing Klf1+/- mice with Klf1H350R/+ mice that harbour a missense mutation in linker-2. Klf1H350R/- mice exhibit severe hemolysis without thalassemia. RNA-seq demonstrate loss of expression of genes encoding transmembrane and cytoskeletal proteins, but not globins. ChIP-seq show no change in DNA-binding specificity, but a global reduction in affinity, which is confirmed using recombinant proteins and in vitro binding assays. This study provides new insights into how linker mutations in zinc finger transcription factors result in different phenotypes to those caused by loss-of-function mutations.
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Affiliation(s)
- Stephen Huang
- Mater Research Institute - UQ, The University of Queensland, St Lucia, Australia
- School of Biomedical Sciences, The University of Queensland, St Lucia, Australia
| | - Casie Reed
- Australian Centre for Blood Diseases, Monash University, Clayton, Australia
| | - Melissa Ilsley
- Mater Research Institute - UQ, The University of Queensland, St Lucia, Australia
- School of Biomedical Sciences, The University of Queensland, St Lucia, Australia
| | - Graham Magor
- Mater Research Institute - UQ, The University of Queensland, St Lucia, Australia
- Australian Centre for Blood Diseases, Monash University, Clayton, Australia
| | - Michael Tallack
- Mater Research Institute - UQ, The University of Queensland, St Lucia, Australia
| | - Michael Landsberg
- School of Chemistry and Molecular Biosciences, The University of Queensland, St Lucia, Australia
| | - Helen Mitchell
- Australian Centre for Blood Diseases, Monash University, Clayton, Australia
| | - Kevin Gillinder
- Mater Research Institute - UQ, The University of Queensland, St Lucia, Australia
- Australian Centre for Blood Diseases, Monash University, Clayton, Australia
| | - Andrew Perkins
- Mater Research Institute - UQ, The University of Queensland, St Lucia, Australia.
- School of Biomedical Sciences, The University of Queensland, St Lucia, Australia.
- Australian Centre for Blood Diseases, Monash University, Clayton, Australia.
- Department of Haematology, The Alfred Hospital, Melbourne, Australia.
- Biodiscovery Institute, Monash University, Clayton, Australia.
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3
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Noulsri E, Lerdwana S, Palasuwan D, Palasuwan A. Diagnostic Performance of 10 Mathematical Formulae for Identifying Blood Donors with Thalassemia Trait. Lab Med 2023; 54:593-597. [PMID: 36932722 DOI: 10.1093/labmed/lmad011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023] Open
Abstract
OBJECTIVE To compare the diagnostic performance of 10 mathematical formulae for identifying thalassemia trait in blood donors. METHODS Compete blood counts were conducted on peripheral blood specimens using the UniCel DxH 800 hematology analyzer. Receiver operating characteristic curves were used to evaluate the diagnostic performance of each mathematical formula. RESULTS In the 66 donors with thalassemia and 288 subjects with no thalassemia analyzed, donors with thalassemia trait had lower values for mean corpuscular volume and mean corpuscular hemoglobin than subjects without thalassemia donors (77 fL vs 86 fL [P < .001]; 25 pg vs 28 pg [P < .001]). The formula developed by Shine and Lal in 1977 showed the highest area under the curve value, namely, 0.9. At the cutoff value of <1812, this formula had maximum specificity of 82.35% and sensitivity of 89.58%. CONCLUSIONS Our data indicate that the Shine and Lal formula has remarkable diagnostic performance in identifying donors with underlying thalassemia trait.
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Affiliation(s)
| | - Surada Lerdwana
- Biomedical Research Incubator Unit, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Duangdao Palasuwan
- Oxidation in Red Cell Disorders Research Unit, Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
| | - Attakorn Palasuwan
- Oxidation in Red Cell Disorders Research Unit, Department of Clinical Microscopy, Faculty of Allied Health Sciences, Chulalongkorn University, Bangkok, Thailand
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Abstract
Thalassemia syndromes are common monogenic disorders and represent a significant health issue worldwide. In this review, the authors elaborate on fundamental genetic knowledge about thalassemias, including the structure and location of globin genes, the production of hemoglobin during development, the molecular lesions causing α-, β-, and other thalassemia syndromes, the genotype-phenotype correlation, and the genetic modifiers of these conditions. In addition, they briefly discuss the molecular techniques applied for diagnosis and innovative cell and gene therapy strategies to cure these conditions.
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Affiliation(s)
- Nicolò Tesio
- Department of Clinical and Biological Sciences, San Luigi Gonzaga University Hospital, University of Torino, Regione Gonzole, 10, 10043 Orbassano, Turin, Italy. https://twitter.com/nicolotesio
| | - Daniel E Bauer
- Division of Hematology/Oncology, Boston Children's Hospital, Boston, MA, USA; Department of Pediatric Oncology, Dana-Farber Cancer Institute, Boston, MA, USA; Department of Pediatrics, Harvard Stem Cell Institute, Broad Institute, Harvard Medical School, Boston, MA, USA.
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5
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Catapano R, Sessa R, Trombetti S, Cesaro E, Russo F, Izzo P, Makis A, Grosso M. Identification and Functional Analysis of Known and New Mutations in the Transcription Factor KLF1 Linked with β-Thalassemia-like Phenotypes. BIOLOGY 2023; 12:biology12040510. [PMID: 37106711 PMCID: PMC10135830 DOI: 10.3390/biology12040510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Revised: 03/16/2023] [Accepted: 03/24/2023] [Indexed: 03/31/2023]
Abstract
The erythroid transcriptional factor Krüppel-like factor 1 (KLF1) is a master regulator of erythropoiesis. Mutations that cause KLF1 haploinsufficiency have been linked to increased fetal hemoglobin (HbF) and hemoglobin A2 (HbA2) levels with ameliorative effects on the severity of β-thalassemia. With the aim of determining if KLF1 gene variations might play a role in the modulation of β-thalassemia, in this study we screened 17 subjects showing a β-thalassemia-like phenotype with a slight or marked increase in HbA2 and HbF levels. Overall, seven KLF1 gene variants were identified, of which two were novel. Functional studies were performed in K562 cells to clarify the pathogenic significance of these mutations. Our study confirmed the ameliorative effect on the thalassemia phenotype for some of these variants but also raised the notion that certain mutations may have deteriorating effects by increasing KLF1 expression levels or enhancing its transcriptional activity. Our results indicate that functional studies are required to evaluate the possible effects of KLF1 mutations, particularly in the case of the co-existence of two or more mutations that could differently contribute to KLF1 expression or transcriptional activity and consequently to the thalassemia phenotype.
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Affiliation(s)
- Rosa Catapano
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Raffaele Sessa
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Silvia Trombetti
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
- Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, 80137 Naples, Italy
| | - Elena Cesaro
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Filippo Russo
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Paola Izzo
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
| | - Alexandros Makis
- Department of Pediatrics, University Hospital of Ioannina, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece
| | - Michela Grosso
- Department of Molecular Medicine and Medical Biotechnology, School of Medicine, University of Naples Federico II, 80131 Naples, Italy
- Correspondence:
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Lou J, Ye Y, Sun M, Zhao Y, Fu Y, Liu Y. A stepwise haematological screening and whole-exome sequencing reveal multiple mutations from SUPT5H causing an elevation of Hb A 2 from a cohort of 47336 individuals. Int J Lab Hematol 2023; 45:90-95. [PMID: 36054783 DOI: 10.1111/ijlh.13959] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 08/10/2022] [Indexed: 01/18/2023]
Abstract
INTRODUCTION Though an increase in Hb A2 is one of the most key markers of β-thal carriers, a few independent cases are reported to show elevated Hb A2 levels caused by mutations in other genes beyond β-globin gene. METHODS We reviewed the haematological indices of 47336 individuals to analyse the phenotype-genotype correlation and identified 1439 individuals (3.04%) positive in the elevation of Hb A2 . Globin and KLF1 genes analysis was performed, and further whole-exome sequencing was carried to dissect the genetic causes of those positive samples without β-thalassemic or KLF1 mutations. RESULTS Of these 1439 individuals with elevated Hb A2 , 1381 had a molecular defect in globin genes, and most were β-thalassemic mutation; 10 had a molecular defect in KLF1 gene. Finally, among the 38 individuals without β-thalassemic or KLF1 mutations, 7 were identified to carried a loss-of-function mutation in SUPT5H. CONCLUSION This study has provided a mutation spectrum of SUPT5H in a cohort screening leading to the elevation of Hb A2 . According to the previous observations that individuals with a combination of β-thal mutation and a SUPT5H variant might present moderate β-thaelassemia, these findings emphasized the importance of comprehensive molecular diagnosis to prevent birth defects of β-thaelassemia caused by rare mutations from modifier genes.
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Affiliation(s)
- Jiwu Lou
- Prenatal Diagnostic Center, Dongguan Maternal and Children Health Hospital, Dongguan, Guangdong, People's Republic of China
| | - Yuhua Ye
- Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong, People's Republic of China.,Guangdong Genetics Testing Engineering Research Center, Guangzhou, Guangdong, People's Republic of China.,Innovation Center for Diagnostics and Treatment of Thaelassemia, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, People's Republic of China
| | - Manna Sun
- Department of Obstetrics & Gynecology, Dongguan Maternal and Children Hospital, Dongguan, Guangdong, People's Republic of China
| | - Ying Zhao
- Prenatal Diagnostic Center, Dongguan Maternal and Children Health Hospital, Dongguan, Guangdong, People's Republic of China
| | - Youqing Fu
- Prenatal Diagnostic Center, Dongguan Maternal and Children Health Hospital, Dongguan, Guangdong, People's Republic of China
| | - Yanhui Liu
- Prenatal Diagnostic Center, Dongguan Maternal and Children Health Hospital, Dongguan, Guangdong, People's Republic of China
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7
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Krüppel-Like Factor 1: A Pivotal Gene Regulator in Erythropoiesis. Cells 2022; 11:cells11193069. [PMID: 36231031 PMCID: PMC9561966 DOI: 10.3390/cells11193069] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Revised: 09/21/2022] [Accepted: 09/26/2022] [Indexed: 11/17/2022] Open
Abstract
Krüppel-like factor 1 (KLF1) plays a crucial role in erythropoiesis. In-depth studies conducted on mice and humans have highlighted its importance in erythroid lineage commitment, terminal erythropoiesis progression and the switching of globin genes from γ to β. The role of KLF1 in haemoglobin switching is exerted by the direct activation of β-globin gene and by the silencing of γ-globin through activation of BCL11A, an important γ-globin gene repressor. The link between KLF1 and γ-globin silencing identifies this transcription factor as a possible therapeutic target for β-hemoglobinopathies. Moreover, several mutations have been identified in the human genes that are responsible for various benign phenotypes and erythroid disorders. The study of the phenotype associated with each mutation has greatly contributed to the current understanding of the complex role of KLF1 in erythropoiesis. This review will focus on some of the principal functions of KLF1 on erythroid cell commitment and differentiation, spanning from primitive to definitive erythropoiesis. The fundamental role of KLF1 in haemoglobin switching will be also highlighted. Finally, an overview of the principal human mutations and relative phenotypes and disorders will be described.
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8
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Nuinoon M, Rattanaporn P, Benjchareonwong T, Choowet A, Suwanno K, Saekoo N, Lekpetch K, Thipthara O, Svasti S, Fucharoen S. Genetic predictions of life expectancy in southern Thai patients with β0‑thalassemia/Hb E. Biomed Rep 2022; 16:52. [PMID: 35620315 PMCID: PMC9112403 DOI: 10.3892/br.2022.1535] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Accepted: 04/20/2022] [Indexed: 01/19/2023] Open
Abstract
The types of β-thalassemia mutations, α-thalassemia interactions, and Hb F-associated SNPs have been described in association with variable disease phenotypes. This study aimed to determine the updated spectrum of β-thalassemia mutations and evaluate the contribution of primary and secondary genetic modifiers and SNPs to disease severity, age at onset, and predicted life expectancy in southern Thai β-thalassemia patients. A total of 181 β-thalassemia patients were enrolled and 135 β0-thalassemia/Hb E patients without α-thalassemia interactions were divided into three categories according to disease severity, age at onset, and predicted life expectancy. A total of 16 β-thalassemia mutations were identified in this study, and the three most common β-thalassemia mutations accounted for 61.4% of all mutations. It was also found that the XmnI polymorphism and rs2071348 were associated with age at onset and the predicted life expectancy. More than 82% of β0-thalassemia/Hb E patients with CC genotype (XmnI) were 3 years old or younger at onset. Additionally, >90% of the higher predicted life expectancy in β0-thalassemia/Hb E patients had the T allele of XmnI. Therefore, genetic prediction for age at onset and life expectancy is beneficial and practical during prenatal diagnosis or newborn screening for better genetic counseling and optimal management.
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Affiliation(s)
- Manit Nuinoon
- Hematology and Transfusion Science Research Center, Walailak University, Nakhon Si Thammarat 80160, Thailand
| | - Patchara Rattanaporn
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom 73170, Thailand
| | - Thongchai Benjchareonwong
- Department of Clinical Pathology and Anatomy, Chumphon Ket‑Udomsak Hospital, Chumphon 86000, Thailand
| | - Anuchit Choowet
- Department of Pediatrics, Vachira Phuket Hospital, Phuket 83000, Thailand
| | - Komsai Suwanno
- Department of Internal Medicine, Hatyai Hospital, Songkhla 90110, Thailand
| | - Ngamta Saekoo
- Department of Internal Medicine, Hatyai Hospital, Songkhla 90110, Thailand
| | - Krongjit Lekpetch
- Department of Pediatrics, Suratthani Hospital, Suratthani 84000, Thailand
| | - Orapan Thipthara
- Department of Pediatrics, Maharaj Nakhon Si Thammarat Hospital, Nakhon Si Thammarat 80000, Thailand
| | - Saovaros Svasti
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom 73170, Thailand
| | - Suthat Fucharoen
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon Pathom 73170, Thailand
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9
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Epigenomic analysis of KLF1 haploinsufficiency in primary human erythroblasts. Sci Rep 2022; 12:336. [PMID: 35013432 PMCID: PMC8748495 DOI: 10.1038/s41598-021-04126-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2021] [Accepted: 12/16/2021] [Indexed: 12/13/2022] Open
Abstract
Haploinsufficiency for the erythroid-specific transcription factor KLF1 is associated with hereditary persistence of fetal hemoglobin (HPFH). Increased HbF ameliorates the symptoms of β-hemoglobinopathies and downregulation of KLF1 activity has been proposed as a potential therapeutic strategy. However, the feasibility of this approach has been challenged by the observation that KLF1 haploinsufficient individuals with the same KLF1 variant, within the same family, display a wide range of HbF levels. This phenotypic variability is not readily explained by co-inheritance of known HbF-modulating variants in the HBB, HBS1L-MYB and/or BCL11A loci. We studied cultured erythroid progenitors obtained from Maltese individuals in which KLF1 p.K288X carriers display HbF levels ranging between 1.3 and 12.3% of total Hb. Using a combination of gene expression analysis, chromatin accessibility assays and promoter activity tests we find that variation in expression of the wildtype KLF1 allele may explain a significant part of the variability in HbF levels observed in KLF1 haploinsufficiency. Our results have general bearing on the variable penetrance of haploinsufficiency phenotypes and on conflicting interpretations of pathogenicity of variants in other transcriptional regulators such as EP300, GATA2 and RUNX1.
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10
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Charnay T, Cerino M, Gonnet K, Bonello-Palot N, Bréchard MP, Badens C. A novel SUPT5H variant associated with a beta-thalassaemia trait. Br J Haematol 2021; 196:e70-e71. [PMID: 34854076 DOI: 10.1111/bjh.17985] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 11/22/2021] [Indexed: 12/01/2022]
Affiliation(s)
- Theo Charnay
- Department of genetics, APHM, Marseille, France.,Aix Marseille Univ, MMG, U 1251, Marseille, France
| | - Mathieu Cerino
- Department of genetics, APHM, Marseille, France.,Aix Marseille Univ, MMG, U 1251, Marseille, France
| | | | - Nathalie Bonello-Palot
- Department of genetics, APHM, Marseille, France.,Aix Marseille Univ, MMG, U 1251, Marseille, France
| | | | - Catherine Badens
- Department of genetics, APHM, Marseille, France.,Aix Marseille Univ, MMG, U 1251, Marseille, France
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11
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Tangsricharoen T, Natesirinilkul R, Phusua A, Fanhchaksai K, Ittiwut C, Chetruengchai W, Juntharaniyom M, Charoenkwan P, Viprakasit V, Phokaew C, Shotelersuk V. Severe neonatal haemolytic anaemia caused by compound heterozygous KLF1 mutations: report of four families and literature review. Br J Haematol 2021; 194:626-634. [PMID: 34227100 DOI: 10.1111/bjh.17616] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 05/06/2021] [Accepted: 05/13/2021] [Indexed: 01/01/2023]
Abstract
Mutations in the KLF1 gene, which encodes a transcription factor playing a role in erythropoiesis, have recently been demonstrated to be a rare cause of hereditary haemolytic anaemia. We described the genotypic and phenotypic spectra of four unrelated families with compound heterozygous class 2/class 3 KLF1 mutations. All patients had p.G176RfsX179 on one allele and either p.A298P, p.R301H or p.G335R on the other allele. All presented on the first day of life with severe haemolytic anaemia with abnormal red blood cell morphology, markedly increased nucleated red blood cells and hyperbilirubinaemia. Three patients later became transfusion-dependent. All parents with heterozygous KLF1 mutation without co-inherited thalassaemia had normal to borderline mean corpuscular volume (MCV) and normal to slightly elevated Hb F. Fifteen previously reported cases of biallelic KLF1 mutations were identified from a literature review. All except one presented with severe haemolytic anaemia in the neonatal period. Our finding substantiates that compound heterozygous KLF1 mutations are associated with severe neonatal haemolytic anaemia and expands the haematologic phenotypic spectrum. In carriers, the previously suggested findings of low MCV, high Hb A2 and high Hb F are inconsistent; thus this necessitates molecular studies for the identification of carriers.
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Affiliation(s)
- Tanu Tangsricharoen
- Department of Pediatrics, Division of Hematology and Oncology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Rungrote Natesirinilkul
- Department of Pediatrics, Division of Hematology and Oncology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Arunee Phusua
- Department of Pediatrics, Division of Hematology and Oncology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Kanda Fanhchaksai
- Department of Pediatrics, Division of Hematology and Oncology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Chupong Ittiwut
- Department of Pediatrics, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
| | - Wanna Chetruengchai
- Department of Pediatrics, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
| | - Monthana Juntharaniyom
- Department of Pediatrics, Division of Hematology and Oncology, Khon Kaen Regional Hospital, Khon Kaen, Thailand
| | - Pimlak Charoenkwan
- Department of Pediatrics, Division of Hematology and Oncology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand
| | - Vip Viprakasit
- Department of Pediatrics, Division of Hematology and Oncology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Chureerat Phokaew
- Department of Pediatrics, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
| | - Vorasuk Shotelersuk
- Department of Pediatrics, Center of Excellence for Medical Genomics, Medical Genomics Cluster, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand.,Excellence Center for Genomics and Precision Medicine, King Chulalongkorn Memorial Hospital, The Thai Red Cross Society, Bangkok, Thailand
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12
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Colaco S, Nadkarni A. Borderline HbA 2 levels: Dilemma in diagnosis of beta-thalassemia carriers. MUTATION RESEARCH. REVIEWS IN MUTATION RESEARCH 2021; 788:108387. [PMID: 34893152 DOI: 10.1016/j.mrrev.2021.108387] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2020] [Revised: 05/27/2021] [Accepted: 06/08/2021] [Indexed: 12/17/2022]
Abstract
There is inconsistency in the exact definition of diagnostic levels of HbA2 for β thalassemia trait. While many laboratories consider HbA2 ≥4.0 % diagnostic, still others consider HbA2 ≥3.3 % or HbA2 ≥3.5 % as the cut-off for establishing β thalassemia carrier diagnosis. This is because, over the years, studies have described β thalassemia carriers showing HbA2 levels that lie above the normal range of HbA2 but below the typical carrier range of β thalassemia. These, "borderline HbA2 levels", though not detrimental to health, are significant in β thalassemia carrier diagnosis because they can lead to misinterpretation of results. In this review, we have evaluated the prevalence of borderline HbA2 levels and discussed the causes of borderline HbA2 values. We have also compiled an extensive catalogue of β globin gene defects associated with borderline HbA2 levels and have discussed strategies to avoid misdiagnosing borderline HbA2 β thalassemia carriers. Our analysis of studies that have delineated the cause of borderline HbA2 levels in different populations shows that 35.4 % [626/1766] of all individuals with borderline HbA2 levels carry a molecular defect. Among the positive samples, 17 % [299/1766] show β globin gene defects, 7.7 % [137/1766] show α thalassemia defects, 2.7 % [49/1766] show KLF1 gene mutations, 2.3 % [41/1766] show the co-inheritance of β and α thalassemia, 2.0 % [37/1766] show the co-inheritance of β and δ thalassemia and 1.8 % [32/1766] show α globin gene triplication. It appears that a comprehensive molecular work up of the β globin gene is the only definite method to detect borderline HbA2 β thalassemia carriers, especially in populations with a high prevalence of the disease. The presence of associated genetic or acquired determinants may subsequently be assessed to identify the cause of borderline HbA2.
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Affiliation(s)
- Stacy Colaco
- Department of Hematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, K.E.M. Hospital Campus, Parel, Mumbai, 400 012, India
| | - Anita Nadkarni
- Department of Hematogenetics, ICMR-National Institute of Immunohematology, 13th Floor, K.E.M. Hospital Campus, Parel, Mumbai, 400 012, India.
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13
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Panichchob P, Iamdeelert P, Wongsariya P, Wongsariya P, Wongwattanasanti P, Tepakhan W, Jomoui W. Molecular Spectrum of β-Thalassemia Mutations in Central to Eastern Thailand. Hemoglobin 2021; 45:97-102. [PMID: 33966551 DOI: 10.1080/03630269.2021.1924193] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The aim of this study was to determine the molecular spectrum of β-thalassemia (β-thal) mutations in eastern Thailand. We identified β-thal mutations using allele specific-polymerase chain reaction (ASPCR) and direct DNA sequencing. We found 18 different β-thal mutations in a total of 191 unrelated subjects. Six common β-thal mutations comprised 86.91% of all the mutations, including codons 41/42 (-TTCT) (HBB: c.126_129delCTTT) (35.60%), codon 17 (A>T) (HBB: c.52A>T) (18.85%), -28 (A>G) (HBB: c.-78A>G) (15.71%), IVS-II-654 (C>T) (HBB: c.316-197C>T) (6.28%), IVS-I-1 (G>T) (HBB: c.92+1G>T) (5.76%) and codon 19 (A>G) (HBB:(c.59A>G) (4.71%). In addition, a novel 60 kb deletion in two unrelated cases was characterized and initially suspected to originate from eastern Thailand. Moreover, we demonstrated the molecular spectrum of recent β-thal mutations in Thailand, and data from this study were compared with five reference laboratory centers in Thailand. This study is the first to identify the comprehensive molecular spectrum of β-thal mutations in eastern Thailand, information that may be essential for screening, genetic counseling and prenatal diagnosis (PND) in this region.
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Affiliation(s)
- Prapaporn Panichchob
- Department of Pathology, Maha Chakri Sirindhorn Medical Center, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand
| | | | - Putita Wongsariya
- Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand
| | | | | | - Wanicha Tepakhan
- Department of Pathology, Faculty of Medicine, Prince of Songkla University, Songkhla, Thailand
| | - Wittaya Jomoui
- Department of Pathology, Maha Chakri Sirindhorn Medical Center, Faculty of Medicine, Srinakharinwirot University, Nakhon Nayok, Thailand
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14
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Cyrus C, Vatte C, Chathoth S, Sayed AA, Borgio JF, Alrubaish MA, Alfalah R, Alsaikhan J, Al Ali AK. Haemoglobin switching modulator SNPs rs5006884 is associated with increased HbA 2 in β-thalassaemia carriers. Arch Med Sci 2021; 17:1064-1074. [PMID: 34336034 PMCID: PMC8314410 DOI: 10.5114/aoms.2019.86705] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 05/15/2018] [Indexed: 11/25/2022] Open
Abstract
INTRODUCTION Haemoglobin A2 (HbA2), the tetramer of α- and δ-globin chains, is used as a diagnostic biomarker for β-thalassaemia carriers. The HbA2 levels are regulated by the presence of HPFH, δ-thalassaemia, HbA1/2 gene triplication, and variants of KLF1, β-globin gene, and HbF regulating QTLs. Saudi Arabia has a high incidence of borderline HbA2 levels, thereby making it difficult to classify the haemoglobinopathies. This study aims to investigate the association of known HbF enhancer QTL gene SNPs with HbA2 levels. MATERIAL AND METHODS 14 Specific SNPs in BCL11A, HMIP, OR51B6, HBBP1, and HBG2 loci were genotyped in 164 Saudi β-thalassaemia carriers by TaqMan assay to validate their role as regulators of HbA2 levels. HbA2 levels were determined using the Variant II β-Thalassemia Short Program Recorder kit. The non-random association of these SNPs was tested using HaploView software. Protein interaction was assessed using 3D structure modelling for OR51B6 (rs5006884), comparative energy minimisation, and root-mean-square deviation (RMSD) prediction. RESULTS Elevated HbA2 levels were associated with SNPs in HBBP1, OR51B6, and TCT haplotype from HBG2 promoter region. The bioinformatics modelling and prediction revealed that the exonic rs5006884 had RMSD value deviations and significantly varied binding energy minimisation. α-globin variations were found in 57.92% of individuals but were not associated with elevated HbA2. CONCLUSIONS The haemoglobin switching modulators rs2071348, rs7482144, and rs5006884 are involved in regulation of HbA2 level with rs5006884 influencing the tetramer formation. Screening for haemoglobinopathies should take these SNPs into consideration, specifically in borderline HbA2 cases. Assiduous analysis of rs5006884 as HbA2 modulator for amelioration of disease severity is recommended.
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Affiliation(s)
- Cyril Cyrus
- Department of Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Chittibabu Vatte
- Department of Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Shahanas Chathoth
- Department of Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Abdul Azeez Sayed
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - J. Francis Borgio
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | | | - Rawan Alfalah
- King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Jana Alsaikhan
- King Fahd Hospital of the University, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
| | - Amein K. Al Ali
- Department of Biochemistry, College of Medicine, Imam Abdulrahman Bin Faisal University, Dammam, Saudi Arabia
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15
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Satthakarn S, Panyasai S, Pornprasert S. Molecular Characterization of β- and α-Globin Gene Mutations in Individuals with Borderline Hb A 2 Levels. Hemoglobin 2020; 44:349-353. [PMID: 33023363 DOI: 10.1080/03630269.2020.1826327] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Elevated Hb A2 level (≥4.0%) is considered to be reliable parameter to identify β-thalassemia (β-thal) carriers. However, some β-thal carriers have been misdiagnosed as their Hb A2 levels are below 4.0%. In addition, coinheritance of α-thalassemia (α-thal) and β-thal might affect Hb A2 levels. Therefore, the aim of this study was to investigate the mutations of β- and α-globin genes in individuals with borderline Hb A2 levels in Thailand. Three hundred samples from individuals with Hb A2 levels of 3.5-3.9% were collected for molecular diagnosis of β-globin gene mutations. In addition, the α0-thal, α+-thal, Hb Constant Spring (Hb CS, HBA2: c.427T>C), and Hb Paksé (HBA2: c.429A>T) diagnostics were also performed. Sixteen samples (5.33%) had β-globin gene mutations, and codon 41/42 (-TTCT) (HBB: c.126_129delCTTT) was the most prevalent mutation. Ninety-eight samples (32.67%) had α-globin gene mutations including four Hb H (β4)-Hb CS disease, two Hb H disease, 13 heterozygous α0-thal, 11 homozygous α+-thal, two α+-thal/Hb CS, one α+-thal/Hb Paksé, 61 heterozygous α+-thal, and four Hb CS. Furthermore, seven cases of β-thal carriers coinheriting α-thal were observed, and five of them carried Hb H disease. High prevalence of both α- and β-thal in subjects with borderline Hb A2 levels suggested that molecular diagnosis of α- and β-thal should be performed, especially in a high prevalence area of thalasssemia carriers, for accurate diagnosis and genetic counseling to prevent and control new severe thalassemia cases. Moreover, β-thal carriers who coinherited Hb H disease might have reduced Hb A2 levels, leading to a misdiagnosis of β-thal in analysis programs.
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Affiliation(s)
- Surada Satthakarn
- Department of Medical Technology, School of Allied Health Sciences, University of Phayao, Phayao, Thailand
| | - Sitthichai Panyasai
- Department of Medical Technology, School of Allied Health Sciences, University of Phayao, Phayao, Thailand
| | - Sakorn Pornprasert
- Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand
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16
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Tepakhan W, Kanjanaopas S, Srewaradachpisal K. Association Between Genetic Polymorphisms and Hb F Levels in Heterozygous β-Thalassemia 3.5 kb Deletions. Hemoglobin 2020; 44:338-343. [PMID: 32878504 DOI: 10.1080/03630269.2020.1811117] [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
Single nucleotide polymorphisms (SNPs) in several genetic modifying factors have been related to Hb F levels, including Gγ XmnI polymorphism, B-cell lymphoma/leukemia 11 A (BCL11A), HBS1L-MYB intergenic polymorphism (HMIP) and a mutation in the Krüppel-like factor 1 (KLF1). This study aimed to determine whether genetic variability of these modifying factors affects Hb F levels in heterozygous β-thalassemia (β-thal) 3.5 kb deletion (NC_000011.10: g.5224302-5227791del13490bp). A total of 111 β-thal 3.5 kb deletion carriers with Hb F levels ranging from 0.9 to 18.4% was recruited for this study. Genotyping of SNPs including HBG2 rs7482144, HMIP rs4895441 and rs9399137, BCL11A rs4671393 and KLF1 rs2072596 was identified. Multiple regression analyses showed that only two SNPs (HMIP rs4895441 and rs9399137) influenced Hb F levels. Interestingly, a combination of these two SNPs was associated with higher Hb F levels. Our study is the first to demonstrate that the rs4895441, rs9399137 of HMIP are associated with elevated Hb F levels in the heterozygous β-thal 3.5 kb deletion.
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Affiliation(s)
- Wanicha Tepakhan
- Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Sataron Kanjanaopas
- Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand
| | - Korntip Srewaradachpisal
- Department of Pathology, Faculty of Medicine, Prince of Songkla University, Hat Yai, Songkhla, Thailand
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17
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Anwar S, Taslem Mourosi J, Hasan MK, Hosen MJ, Miah MF. Umbilical Cord Blood Screening for the Detection of Common Deletional Mutations of α-Thalassemia in Bangladesh. Hemoglobin 2020; 44:201-210. [PMID: 32605390 DOI: 10.1080/03630269.2020.1784755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
α-Thalassemia (α-thal) is assumed to be very prevalent in Bangladesh. We aimed to assess the prevalence of the disease in the country and provide a model for α-thal newborn screening in Bangladesh. We collected umbilical cord blood (UCB) samples from 413 unrelated newborns in Bangladesh. Demographic information, blood indices, osmotic fragility, serum iron (Fe), and zinc (Zn) levels were evaluated for all the subjects. All subjects underwent a polymerase chain reaction (PCR)-based diagnosis for α-thal status, followed by a multiplex gap-PCR-based identification of the deletion type present. Sixty-seven subjects had at least one α-thal deletion (16.22%). We observed that -α3.7 (rightward), - -SEA (Southeast Asian), -α4.2 (leftward), - -MED (Mediterranean) and - -THAI (Thailand) deletions were the most common α-globin deletions present in the country, with the -α3.7 (n = 37) and - -SEA (n = 18) being most prevalent. The osmotic fragility test (OFT) could predict the presence of α-thal deletions with over 98.0% sensitivity. Complete UCB count analysis revealed significant differences between healthy subjects and subjects with α-thal deletions. Although the iron level was almost the same (108.0 vs. 105.7 µg/dL), a reduced level of Zn (98.6 vs. 71.8 µg/dL, p < 0.01) was observed in the cord blood-derived serum of the subjects with α-thal deletions. Moreover, parental age at the time of delivery, gestational period, and birth weight was lower in the subjects with α-thal deletions. This study provides partial information on the epidemiology of α-thal in Bangladesh and describes a model for α-thal newborn screening in the country.
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Affiliation(s)
- Saeed Anwar
- Department of Genetic Engineering and Biotechnology, School of Life Sciences, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Jarin Taslem Mourosi
- Department of Genetic Engineering and Biotechnology, School of Life Sciences, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Md Kamrul Hasan
- Department of Biochemistry and Molecular Biology, Tejgaon College, National University of Bangladesh, Gazipur, Bangladesh.,Department of Public Health, School of Health and Life Sciences, North South University, Dhaka, Bangladesh
| | - Mohammad Jakir Hosen
- Department of Genetic Engineering and Biotechnology, School of Life Sciences, Shahjalal University of Science and Technology, Sylhet, Bangladesh
| | - Md Faruque Miah
- Department of Genetic Engineering and Biotechnology, School of Life Sciences, Shahjalal University of Science and Technology, Sylhet, Bangladesh
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18
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Manchinu MF, Simbula M, Caria CA, Musu E, Perseu L, Porcu S, Steri M, Poddie D, Frau J, Cocco E, Manunza L, Barella S, Ristaldi MS. Delta-Globin Gene Expression Is Enhanced in vivo by Interferon Type I. Front Med (Lausanne) 2020; 7:163. [PMID: 32528964 PMCID: PMC7256663 DOI: 10.3389/fmed.2020.00163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 04/09/2020] [Indexed: 12/19/2022] Open
Abstract
Beta hemoglobinopathies are widely spread monogenic lethal diseases. Delta-globin gene activation has been proposed as a possible approach for curing these pathologies. The therapeutic potential of delta-globin, the non-alpha component of Hemoglobin A2 (α2δ2; HbA2), has been demonstrated in a mouse model of beta thalassemia, while its anti-sickling effect, comparable to that of gamma globin, was established some time ago. Here we show that the delta-globin mRNA level is considerably increased in a Deoxyribonuclease II-alpha knockout mouse model in which type 1 interferon (interferon beta, IFNb) is activated. IFNb activation in the fetal liver improves the delta-globin mRNA level, while the beta-globin mRNA level is significantly reduced. In addition, we show that HbA2 is significantly increased in patients with multiple sclerosis under type 1 interferon treatment. Our results represent a proof of principle that delta-globin expression can be enhanced through the use of molecules. This observation is potentially interesting in view of a pharmacological approach able to increase the HbA2 level.
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Affiliation(s)
- Maria Francesca Manchinu
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Michela Simbula
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Cristian Antonio Caria
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Ester Musu
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Lucia Perseu
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Susanna Porcu
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Maristella Steri
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Daniela Poddie
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
| | - Jessica Frau
- Department of Medical Science and Public Health, Centro Sclerosi Multipla, University of Cagliari, Cagliari, Italy
| | - Eleonora Cocco
- Department of Medical Science and Public Health, Centro Sclerosi Multipla, University of Cagliari, Cagliari, Italy
| | - Laura Manunza
- Ospedale Microcitemico "A. Cao" - A.O. "G. Brotzu", Cagliari, Italy
| | - Susanna Barella
- Ospedale Microcitemico "A. Cao" - A.O. "G. Brotzu", Cagliari, Italy
| | - Maria Serafina Ristaldi
- Istituto Di Ricerca Genetica e Biomedica Del Consiglio Nazionale Delle Ricerche, Monserrato, Italy
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19
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A Krüppel-like factor 1 ( KLF1) Mutation Associated with Severe Congenital Dyserythropoietic Anemia Alters Its DNA-Binding Specificity. Mol Cell Biol 2020; 40:MCB.00444-19. [PMID: 31818881 DOI: 10.1128/mcb.00444-19] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2019] [Accepted: 12/04/2019] [Indexed: 11/20/2022] Open
Abstract
Krüppel-like factor 1 (KLF1/EKLF) is a transcription factor that globally activates genes involved in erythroid cell development. Various mutations are identified in the human KLF1 gene. The E325K mutation causes congenital dyserythropoietic anemia (CDA) type IV, characterized by severe anemia and non-erythroid-cell-related symptoms. The CDA mutation is in the second zinc finger of KLF1 at a position functionally involved in its interactions with DNA. The molecular parameters of how CDA-KLF1 exerts its biological effects have not been addressed. Here, using an in vitro selection strategy, we determined the preferred DNA-binding site for CDA-KLF1. Binding to the deduced consensus sequence is supported by in vitro gel shifts and by in vivo functional reporter gene studies. Two significant changes compared to wild-type (WT) binding are observed: G is selected as the middle nucleotide, and the 3' portion of the consensus sequence is more degenerate. As a consequence, CDA-KLF1 did not bind the WT consensus sequence. However, activation of ectopic sites is promoted. Continuous activation of WT target genes occurs if they fortuitously contain the novel CDA site nearby. Our findings provide a molecular understanding of how a single mutation in the KLF1 zinc finger exerts effects on erythroid physiology in CDA type IV.
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20
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Noor FA, Sultana N, Bhuyan GS, Islam MT, Hossain M, Sarker SK, Islam K, Khan WA, Rahman M, Qadri SK, Shekhar HU, Qadri F, Qadri SS, Mannoor K. Nationwide carrier detection and molecular characterization of β-thalassemia and hemoglobin E variants in Bangladeshi population. Orphanet J Rare Dis 2020; 15:15. [PMID: 31941534 PMCID: PMC6961315 DOI: 10.1186/s13023-020-1294-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Accepted: 01/02/2020] [Indexed: 12/30/2022] Open
Abstract
Background ß-thalassemia is one of the most common inherited blood disorders in the world and a major deterrent to the public health of Bangladesh. The management of thalassemia patients requires lifelong frequent blood transfusion and the available treatment options are unsatisfactory. A national policy on thalassemia prevention is mandatory in Bangladesh. However, precise and up-to-date information on the frequency of ß-thalassemia carriers are missing due to lack of accurate diagnostic approaches, limited access to information and absence of national screening program. This study aims to determine the nationwide carrier frequency of hemoglobin E (HbE) and β- thalassemia and mutation spectrum among the carriers using molecular, hematological and biochemical methods. Methods The study enrolled a total of 1877 individuals (60.1% male and 39.9% female) aged between 18 and 35 years. Total sample size and its division-wise breakdown were calculated in proportion to national and division-wise population. Venous blood was collected and subjected to CBC analysis and Hb-electrophoresis for each participant. Serum ferritin was measured to detect coexistence of iron deficiency anemia with thalassemia carrier. DNA-based High Resolution Melting (HRM) curve analysis was performed for confirmation of carrier status by mutation detection. Results Of 11.89% (95% CI, 10.43–13.35) carriers of β-globin gene mutations, 8.68% (95% CI, 7.41–9.95) had HbE trait (ETT) and 2.24% (95% CI, 1.57–2.91) had beta-thalassemia trait (BTT). Among eight divisions, Rangpur had the highest carrier frequency of 27.1% (ETT-25%, BTT-2.1%), whereas Khulna had the lowest frequency of 4.2% (ETT-4.2% only). Moreover, α- thalassemia, HbD trait, HbE disease, hereditary persistence of HbF were detected in 0.11, 0.16, 0.43 and 0.16% participants, respectively. HRM could identify two individuals with reported pathogenic mutations in both alleles who were erroneously interpreted as carriers by hematological indices. Finally, a total of nine different mutations including a novel mutation (c.151A > G) were detected in the β-globin gene. Conclusions Since carrier frequency for both HbE and β-thalassemia is alarmingly high in Bangladesh, a nationwide awareness and prevention program should be made mandatory to halt the current deteriorating situations. Mutation-based confirmation is highly recommended for the inconclusive cases with conventional carrier screening methods to avoid any faulty detection of thalassemia carriers.
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Affiliation(s)
- Farjana Akther Noor
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh.,Department of Biochemistry and Molecular Biology, University of Dhaka, Shahbagh, Dhaka, 1000, Bangladesh
| | - Nusrat Sultana
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh.,Department of Virology, Dhaka Medical College Hospital, Shahbagh, Dhaka, 1000, Bangladesh
| | - Golam Sarower Bhuyan
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh
| | - Md Tarikul Islam
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh
| | - Mohabbat Hossain
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh
| | - Suprovath Kumar Sarker
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh
| | - Khaleda Islam
- Directorate General of Health Services, MoHFW, Government of Bangladesh, Mohakhali, Dhaka, 1212, Bangladesh
| | - Waqar Ahmed Khan
- Department of Biochemistry and Molecular Biology, Dhaka Shishu Hospital, Sher-e-Bangla Nagar, Dhaka, 1207, Bangladesh
| | - Mujahida Rahman
- Department of Hematology, Bangabandhu Sheikh Mujib Medical University, Shahbagh, Dhaka, 1000, Bangladesh
| | - Syeda Kashfi Qadri
- Department of Pediatric Medicine, KK Women's and Children's Hospital, 100 Bukit Timah Road, Singapore, Singapore
| | - Hossain Uddin Shekhar
- Department of Biochemistry and Molecular Biology, University of Dhaka, Shahbagh, Dhaka, 1000, Bangladesh
| | - Firdausi Qadri
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh.,Department of Enteric and Respiratory Infectious Diseases, Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Mohakhali, Dhaka, 1212, Bangladesh
| | - Syed Saleheen Qadri
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh
| | - Kaiissar Mannoor
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, 1212, Bangladesh.
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21
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Fanis P, Kousiappa I, Phylactides M, Kyrri A, Hadjigavriel M, Christou S, Sitarou M, Kleanthous M. A novel mutation in the erythroid transcription factor KLF1 is likely responsible for ameliorating β-thalassemia major. Hum Mutat 2019; 40:1768-1780. [PMID: 31115947 PMCID: PMC6790707 DOI: 10.1002/humu.23817] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Revised: 05/02/2019] [Accepted: 05/05/2019] [Indexed: 12/02/2022]
Abstract
We describe the identification of a novel missense mutation in the second zinc finger of KLF1 in two siblings who, based on their genotype, are predicted to suffer from beta thalassemia major but are, in fact, transfusion‐free and in good health. These individuals, as well as two additional members of the same family also carrying this KLF1 mutation, exhibit high levels of fetal hemoglobin (HbF). KLF1 is an erythroid transcription factor, which plays a critical role in the regulation of the developmental switch between fetal and adult hemoglobin by regulating the expression of a multitude of genes including that of BCL11A. The mutation appears to be the main candidate responsible for the beta thalassemia‐ameliorating effect as this segregates with the observed phenotype and also exogenous expression of the KLF1 mutant protein in human erythroid progenitor cells resulted in the induction of γ‐globin, without, however, affecting BCL11A levels. This report adds to the weight of evidence that heterozygous KLF1 mutations can ameliorate the severity of the β‐thalassemia major phenotype.
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Affiliation(s)
- Pavlos Fanis
- Molecular Genetics Thalassaemia Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Ioanna Kousiappa
- Molecular Genetics Thalassaemia Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Marios Phylactides
- Molecular Genetics Thalassaemia Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
| | - Andreani Kyrri
- Population Screening Laboratory, Archbishop Makarios III Hospital, Nicosia, Cyprus
| | | | | | - Maria Sitarou
- Thalassaemia Clinic, Larnaca General Hospital, Larnaca, Cyprus
| | - Marina Kleanthous
- Molecular Genetics Thalassaemia Department, The Cyprus Institute of Neurology and Genetics, Nicosia, Cyprus
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22
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Ilsley MD, Huang S, Magor GW, Landsberg MJ, Gillinder KR, Perkins AC. Corrupted DNA-binding specificity and ectopic transcription underpin dominant neomorphic mutations in KLF/SP transcription factors. BMC Genomics 2019; 20:417. [PMID: 31126231 PMCID: PMC6534859 DOI: 10.1186/s12864-019-5805-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2018] [Accepted: 05/17/2019] [Indexed: 02/07/2023] Open
Abstract
Background Mutations in the transcription factor, KLF1, are common within certain populations of the world. Heterozygous missense mutations in KLF1 mostly lead to benign phenotypes, but a heterozygous mutation in a DNA-binding residue (E325K in human) results in severe Congenital Dyserythropoietic Anemia type IV (CDA IV); i.e. an autosomal-dominant disorder characterized by neonatal hemolysis. Results To investigate the biochemical and genetic mechanism of CDA IV, we generated murine erythroid cell lines that harbor tamoxifen-inducible (ER™) versions of wild type and mutant KLF1 on a Klf1−/− genetic background. Nuclear translocation of wild type KLF1 results in terminal erythroid differentiation, whereas mutant KLF1 results in hemolysis without differentiation. The E to K variant binds poorly to the canonical 9 bp recognition motif (NGG-GYG-KGG) genome-wide but binds at high affinity to a corrupted motif (NGG-GRG-KGG). We confirmed altered DNA-binding specificity by quantitative in vitro binding assays of recombinant zinc-finger domains. Our results are consistent with previously reported structural data of KLF-DNA interactions. We employed 4sU-RNA-seq to show that a corrupted transcriptome is a direct consequence of aberrant DNA binding. Conclusions Since all KLF/SP family proteins bind DNA in an identical fashion, these results are likely to be generally applicable to mutations in all family members. Importantly, they explain how certain mutations in the DNA-binding domain of transcription factors can generate neomorphic functions that result in autosomal dominant disease. Electronic supplementary material The online version of this article (10.1186/s12864-019-5805-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Melissa D Ilsley
- Mater Research, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Stephen Huang
- Mater Research, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia.,School of Biomedical Sciences, University of Queensland, Brisbane, QLD, Australia
| | - Graham W Magor
- Mater Research, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia.,Australian Centre for Blood Diseases, Monash University, Melbourne, VIC, Australia
| | - Michael J Landsberg
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, QLD, Australia
| | - Kevin R Gillinder
- Mater Research, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia. .,Australian Centre for Blood Diseases, Monash University, Melbourne, VIC, Australia.
| | - Andrew C Perkins
- Mater Research, Translational Research Institute, University of Queensland, Brisbane, QLD, Australia.,Australian Centre for Blood Diseases, Monash University, Melbourne, VIC, Australia
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23
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Genetic Variants Within the Erythroid Transcription Factor, KLF1, and Reduction of the Expression of Lutheran and Other Blood Group Antigens: Review of the In(Lu) Phenotype. Transfus Med Rev 2019; 33:111-117. [DOI: 10.1016/j.tmrv.2019.01.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2018] [Revised: 01/22/2019] [Accepted: 01/30/2019] [Indexed: 11/22/2022]
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24
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Cantú I, van de Werken HJG, Gillemans N, Stadhouders R, Heshusius S, Maas A, Esteghamat F, Ozgur Z, van IJcken WFJ, Grosveld F, von Lindern M, Philipsen S, van Dijk TB. The mouse KLF1 Nan variant impairs nuclear condensation and erythroid maturation. PLoS One 2019; 14:e0208659. [PMID: 30921348 PMCID: PMC6438607 DOI: 10.1371/journal.pone.0208659] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Accepted: 03/11/2019] [Indexed: 12/13/2022] Open
Abstract
Krüppel-like factor 1 (KLF1) is an essential transcription factor for erythroid development, as demonstrated by Klf1 knockout mice which die around E14 due to severe anemia. In humans, >140 KLF1 variants, causing different erythroid phenotypes, have been described. The KLF1 Nan variant, a single amino acid substitution (p.E339D) in the DNA binding domain, causes hemolytic anemia and is dominant over wildtype KLF1. Here we describe the effects of the KLF1 Nan variant during fetal development. We show that Nan embryos have defects in erythroid maturation. RNA-sequencing of the KLF1 Nan fetal liver cells revealed that Exportin 7 (Xpo7) was among the 782 deregulated genes. This nuclear exportin is implicated in terminal erythroid differentiation; in particular it is involved in nuclear condensation. Indeed, KLF1 Nan fetal liver cells had larger nuclei and reduced chromatin condensation. Knockdown of XPO7 in wildtype erythroid cells caused a similar phenotype. We propose that reduced expression of XPO7 is partially responsible for the erythroid defects observed in KLF1 Nan erythroid cells.
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Affiliation(s)
- Ileana Cantú
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | | | - Nynke Gillemans
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | | | - Steven Heshusius
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
- Department of Hematopoiesis, Sanquin Research, Amsterdam, The Netherlands
| | - Alex Maas
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | | | - Zeliha Ozgur
- Center for Biomics, Erasmus MC, Rotterdam, The Netherlands
| | | | - Frank Grosveld
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
| | | | - Sjaak Philipsen
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands
- * E-mail:
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25
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Barbarani G, Fugazza C, Strouboulis J, Ronchi AE. The Pleiotropic Effects of GATA1 and KLF1 in Physiological Erythropoiesis and in Dyserythropoietic Disorders. Front Physiol 2019; 10:91. [PMID: 30809156 PMCID: PMC6379452 DOI: 10.3389/fphys.2019.00091] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 01/25/2019] [Indexed: 01/19/2023] Open
Abstract
In the last few years, the advent of new technological approaches has led to a better knowledge of the ontogeny of erythropoiesis during development and of the journey leading from hematopoietic stem cells (HSCs) to mature red blood cells (RBCs). Our view of a well-defined hierarchical model of hematopoiesis with a near-homogeneous HSC population residing at the apex has been progressively challenged in favor of a landscape where HSCs themselves are highly heterogeneous and lineages separate earlier than previously thought. The coordination of these events is orchestrated by transcription factors (TFs) that work in a combinatorial manner to activate and/or repress their target genes. The development of next generation sequencing (NGS) has facilitated the identification of pathological mutations involving TFs underlying hematological defects. The examples of GATA1 and KLF1 presented in this review suggest that in the next few years the number of TF mutations associated with dyserythropoietic disorders will further increase.
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Affiliation(s)
- Gloria Barbarani
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi Milano-Bicocca, Milan, Italy
| | - Cristina Fugazza
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi Milano-Bicocca, Milan, Italy
| | - John Strouboulis
- School of Cancer & Pharmaceutical Sciences, Faculty of Life Sciences & Medicine, King's College London, London, United Kingdom
| | - Antonella E Ronchi
- Dipartimento di Biotecnologie e Bioscienze, Università degli Studi Milano-Bicocca, Milan, Italy
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26
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Chaweephisal P, Phusua A, Fanhchaksai K, Sirichotiyakul S, Charoenkwan P. Borderline hemoglobin A2 levels in northern Thai population: HBB genotypes and effects of coinherited alpha-thalassemia. Blood Cells Mol Dis 2019; 74:13-17. [DOI: 10.1016/j.bcmd.2018.10.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Revised: 10/01/2018] [Accepted: 10/03/2018] [Indexed: 01/13/2023]
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27
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Yi X, Liu H, Ou Y, Liu M, Zhu L, Chen H, Zhang J. Dominant inflammatory profile of the placenta in a preterm labor mouse model. J Matern Fetal Neonatal Med 2019; 33:1927-1933. [PMID: 30328754 DOI: 10.1080/14767058.2018.1533949] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Objective: Despite a growing association between inflammation and preterm labor, the underlying mechanisms explaining the development of preterm labor after infection are still poorly understood. Here, we use RNA-sequencing to characterize the transcriptome changes of placenta tissue in a preterm labor mouse model.Materials and methods: On day 15.5 of gestation, BALB/c mice received intrauterine injection of LPS to mimic preterm labor. A comprehensive catalog of genes was obtained using RNA-sequences and followed by bioinformatics analysis. The NOD-like receptor signaling pathway (Nod2, Cxcl1, Cxcl2, and IL-1β) and two downregulated genes (Ctsg and Snca) were selected for validating the results using qPCR analysis.Results: We identified 155 differentially expressed genes (DEGs), 84 biological processes and 45 pathways in the placenta using RNA-seq. Fifty-four biological processes could be categorized as immune-related processes and 33 pathways were mainly related to immune disease and infections. All genes were consistent between the RNA-seq and qPCR analyses.Conclusions: The dominant role for inflammatory biological processes and pathways in placenta can lead to preterm labor.
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Affiliation(s)
- Xiaochun Yi
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Huixiang Liu
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Yuhua Ou
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Meilan Liu
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Liqiong Zhu
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Hui Chen
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
| | - Jianping Zhang
- Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou, China
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28
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Hariharan P, Colah R, Ghosh K, Nadkarni A. Differential role of Kruppel like factor 1 (KLF1) gene in red blood cell disorders. Genomics 2018; 111:1771-1776. [PMID: 30529538 DOI: 10.1016/j.ygeno.2018.11.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Revised: 11/27/2018] [Accepted: 11/30/2018] [Indexed: 01/06/2023]
Abstract
The master erythroid regulator KLF1,plays a pivotal role during erythroid lineage development by regulating the expression of many erythroid genes. Variations in the KLF1 gene are found to be associated with varied erythroid phenotypes. With the aim of determining the role of KLF1 gene variations in HbF induction and their genotype phenotype relationship, in this study, we screened 370 individuals with different hemoglobinopathy condition. Hematological analysis was carried out using automated blood cell counter and Variant II HPLC (Biorad). KLF1 gene mutations were screened using automated DNA sequencing. Expression analysis was carried out using q-RT PCR of KLF1, BCL11A and γ-globin after selective enrichment and culturing of CD 34 +ve cells into an erythroid lineage. Over all 14 KLF1 gene variations were identified, of which six variants were novel. The incidence of KLF1 gene mutations was found to be 8.1%. It was seen that KLF1 mutations contributed in borderline HbA2 levels as 7.6% of our borderline HbA2 cases showed presence of KLF1 variations. It also contributed in induction of HbF levels under stress erythropoietic conditions. Gene expression studies revealed inverse correlation of KLF1, BCL11A (reduced) with γ-globin gene expression (increased) in patients showing KLF1 gene mutations, thus indicating the role of KLF1 gene in regulating the γ-globin gene expression. The identification of genomic variants of the KLF1 may help in determining the functionally active domain of this protein and will facilitate in understanding the wide spectrum of phenotypes generated by these variants.
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Affiliation(s)
- Priya Hariharan
- National Institute of Immunohematology (ICMR), 13th Floor, New Multi-storeyed Building, K.E.M. Hospital Campus, Parel, Mumbai 400012, India
| | - Roshan Colah
- National Institute of Immunohematology (ICMR), 13th Floor, New Multi-storeyed Building, K.E.M. Hospital Campus, Parel, Mumbai 400012, India
| | - Kanjaksha Ghosh
- National Institute of Immunohematology (ICMR), 13th Floor, New Multi-storeyed Building, K.E.M. Hospital Campus, Parel, Mumbai 400012, India
| | - Anita Nadkarni
- National Institute of Immunohematology (ICMR), 13th Floor, New Multi-storeyed Building, K.E.M. Hospital Campus, Parel, Mumbai 400012, India.
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29
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Jiang F, Chen GL, Li J, Zhou JY, Liao C, Li DZ. Analysis of the Genotypes in a Chinese Population with Increased Hb A2and Low Hematological Indices. Hemoglobin 2018; 42:154-158. [DOI: 10.1080/03630269.2018.1509869] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Fan Jiang
- Southern Medical University, Guangzhou Women and Children’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
- Prenatal Diagnostic Center, Guangzhou Women and Children’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Gui-Lan Chen
- Prenatal Diagnostic Center, Guangzhou Women and Children’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Jian Li
- Prenatal Diagnostic Center, Guangzhou Women and Children’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Jian-Ying Zhou
- Prenatal Diagnostic Center, Guangzhou Women and Children’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
| | - Can Liao
- Southern Medical University, Guangzhou Women and Children’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
- Prenatal Diagnostic Center, Guangzhou Women and Children’s 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’s Medical Center affiliated to Guangzhou Medical University, Guangzhou, Guangdong Province, People’s Republic of China
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30
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Fraser NS, Knauth CM, Schoeman EM, Moussa A, Perkins AC, Walsh T, Millard GM, Dean MM, Hyland CA, Flower RL. Investigation of the variable In(Lu) phenotype caused by KLF1 variants. Transfusion 2018; 58:2414-2420. [PMID: 30222867 DOI: 10.1111/trf.14926] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 01/31/2023]
Abstract
INTRODUCTION KLF1 is an essential transcriptional activator that drives erythropoiesis. KLF1 variants can result in the Inhibitor of Lutheran, or In(Lu), phenotype where red blood cells (RBCs) have reduced BCAM (LU) and CD44 (IN). Other RBC surface molecules also have changed expression; however, there is controversy in the literature regarding which are truly impacted. We aimed to investigate KLF1 variants in the Australian population. STUDY DESIGN AND METHODS In(Lu) samples were sourced through screening and through the RBC reference laboratory. Blood donor samples (8036) were screened to identify weakened/absent Lub antigen. Samples were genotyped by massively parallel sequencing, while surface carbohydrates and blood group molecules were assessed by flow cytometry. Hemoglobin (Hb) types were analyzed by high-performance liquid chromatography. RESULTS Four of 8036 donors were identified to be In(Lu), and two previously identified In(Lu) samples were provided from the RBC reference laboratory. Five different KLF1 variants were identified; two were novel: c.954G>C/p.Trp318Cys and c.421C>T/p.Arg141*. BCAM and CD44 were reduced in all samples, consistent with previous reports. As a group, In(Lu) RBCs had reduced CD35 (KN), ICAM4 (LW), and CD147 (OK), and demonstrated increased binding of lectins ECA and SNAI. One In(Lu) sample had elevated HbF and another elevated HbA2. CONCLUSION Different KLF1 variants may potentially produce variable phenotypes. A framework for investigating KLF1 variants and their phenotypic impact has been provided. In the future, given available international databases, further testing algorithms (as advocated here) will allow for correlation of phenotype with genotype and therefore accurately document this variability between KLF1 variants.
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Affiliation(s)
- Nicole S Fraser
- Research and Development, Australian Red Cross Blood Service.,School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Christine M Knauth
- Research and Development, Australian Red Cross Blood Service.,School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | | | - Assia Moussa
- Research and Development, Australian Red Cross Blood Service.,School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Andrew C Perkins
- Australian Centre for Blood Diseases, Monash University, Melbourne, Australia
| | - Terry Walsh
- School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | | | - Melinda M Dean
- Research and Development, Australian Red Cross Blood Service.,School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Catherine A Hyland
- Research and Development, Australian Red Cross Blood Service.,School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
| | - Robert L Flower
- Research and Development, Australian Red Cross Blood Service.,School of Biomedical Science, Faculty of Health, Queensland University of Technology, Brisbane, Australia
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31
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Jiang F, Qu YX, Chen GL, Li J, Zhou JY, Zuo LD, Liao C, Li DZ. KFL1 Gene Variants in α-Thalassemia Individuals with Increased Fetal Hemoglobin in a Chinese Population. Hemoglobin 2018; 42:161-165. [PMID: 30205725 DOI: 10.1080/03630269.2018.1486325] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Krüppel-like factor 1 (KLF1) is a pleiotropic erythroid transcription factor that is a regulator of definitive erythropoiesis. The aim of this study was to detect KLF1 gene variants in α-thalassemia (α-thal) carriers with an increased Hb F level in a Chinese population, and determine the changes of hematological parameters as a result of interactions between KLF1 gene mutations and α-thal. Subjects with α-thal and Hb F levels of ≥1.0% were selected for further investigation. Direct sequencing was used to detect KLF1 gene mutations. Hematological parameters of subjects with α-thal and concomitant KLF1 gene mutations and those with α-thal alone were compared. The KLF1 gene variants were detected in 46 of 275 (16.7%) individuals with α-thal and Hb F levels of ≥1.0%. The detection rate of KLF1 gene mutations rose correspondingly when the Hb F level increased. For α0-thal carriers, significantly lower mean corpuscular volume (MCV) and mean corpuscular hemoglobin (Hb) (MCH) values were observed in KLF1 gene mutation-positive carriers than that in KLF1 gene mutation-free carriers; conversely, significantly higher Hb A2 and Hb F levels were observed in the former condition rather than in the latter condition. The results of this study indicate that KLF1 gene variants are common in Chinese subjects with α-thal and increased Hb F levels, and KLF1 gene mutations decreased the red blood cell (RBC) indices in α-thal carriers as that in normal adults.
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Affiliation(s)
- Fan Jiang
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Yan-Xia Qu
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Gui-Lan Chen
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Jian Li
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Jian-Ying Zhou
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Lian-Dong Zuo
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Can Liao
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
| | - Dong-Zhi Li
- a Guangzhou Women and Children's Medical Center , Guangzhou Medical University , Guangzhou , Guangdong Province , People's Republic of China
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32
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Formulas for the Detection β-Thalassemia Carriers Are Affected by Changes in Red Cell Parameters. Mediterr J Hematol Infect Dis 2018; 10:e2018026. [PMID: 29757336 PMCID: PMC5937978 DOI: 10.4084/mjhid.2018.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 03/12/2018] [Indexed: 12/04/2022] Open
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33
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Huang LY, Li J, Zhang Y, Li DZ. A KLF1
gene mutation causes β-thalassemia minor in a Chinese family. Int J Lab Hematol 2018; 40:e35-e37. [DOI: 10.1111/ijlh.12788] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Accepted: 01/16/2018] [Indexed: 11/29/2022]
Affiliation(s)
- L.-Y. Huang
- Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University; Guangzhou Guangdong China
| | - J. Li
- Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University; Guangzhou Guangdong China
| | | | - D.-Z. Li
- Guangzhou Women and Children Medical Center affiliated to Guangzhou Medical University; Guangzhou Guangdong China
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34
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Pollak NM, Hoffman M, Goldberg IJ, Drosatos K. Krüppel-like factors: Crippling and un-crippling metabolic pathways. JACC Basic Transl Sci 2018; 3:132-156. [PMID: 29876529 PMCID: PMC5985828 DOI: 10.1016/j.jacbts.2017.09.001] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 09/05/2017] [Accepted: 09/06/2017] [Indexed: 12/20/2022]
Abstract
Krüppel-like factors (KLFs) are DNA-binding transcriptional factors that regulate various pathways that control metabolism and other cellular mechanisms. Various KLF isoforms have been associated with cellular, organ or systemic metabolism. Altered expression or activation of KLFs has been linked to metabolic abnormalities, such as obesity and diabetes, as well as with heart failure. In this review article we summarize the metabolic functions of KLFs, as well as the networks of different KLF isoforms that jointly regulate metabolism in health and disease.
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Affiliation(s)
- Nina M. Pollak
- School of Chemistry and Molecular Biosciences, University of Queensland, Brisbane, Queensland, Australia
| | - Matthew Hoffman
- Metabolic Biology Laboratory, Center for Translational Medicine, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
| | - Ira J. Goldberg
- Division of Endocrinology, Diabetes and Metabolism, New York University School of Medicine, New York, New York
| | - Konstantinos Drosatos
- Metabolic Biology Laboratory, Center for Translational Medicine, Department of Pharmacology, Lewis Katz School of Medicine at Temple University, Philadelphia, Pennsylvania
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35
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Islam MT, Sarkar SK, Sultana N, Begum MN, Bhuyan GS, Talukder S, Muraduzzaman AKM, Alauddin M, Islam MS, Biswas PP, Biswas A, Qadri SK, Shirin T, Banu B, Sadya S, Hussain M, Sarwardi G, Khan WA, Mannan MA, Shekhar HU, Chowdhury EK, Sajib AA, Akhteruzzaman S, Qadri SS, Qadri F, Mannoor K. High resolution melting curve analysis targeting the HBB gene mutational hot-spot offers a reliable screening approach for all common as well as most of the rare beta-globin gene mutations in Bangladesh. BMC Genet 2018; 19:1. [PMID: 29295702 PMCID: PMC5751541 DOI: 10.1186/s12863-017-0594-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2017] [Accepted: 12/22/2017] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND Bangladesh lies in the global thalassemia belt, which has a defined mutational hot-spot in the beta-globin gene. The high carrier frequencies of beta-thalassemia trait and hemoglobin E-trait in Bangladesh necessitate a reliable DNA-based carrier screening approach that could supplement the use of hematological and electrophoretic indices to overcome the barriers of carrier screening. With this view in mind, the study aimed to establish a high resolution melting (HRM) curve-based rapid and reliable mutation screening method targeting the mutational hot-spot of South Asian and Southeast Asian countries that encompasses exon-1 (c.1 - c.92), intron-1 (c.92 + 1 - c.92 + 130) and a portion of exon-2 (c.93 - c.217) of the HBB gene which harbors more than 95% of mutant alleles responsible for beta-thalassemia in Bangladesh. RESULTS Our HRM approach could successfully differentiate ten beta-globin gene mutations, namely c.79G > A, c.92 + 5G > C, c.126_129delCTTT, c.27_28insG, c.46delT, c.47G > A, c.92G > C, c.92 + 130G > C, c.126delC and c.135delC in heterozygous states from the wild type alleles, implying the significance of the approach for carrier screening as the first three of these mutations account for ~85% of total mutant alleles in Bangladesh. Moreover, different combinations of compound heterozygous mutations were found to generate melt curves that were distinct from the wild type alleles and from one another. Based on the findings, sixteen reference samples were run in parallel to 41 unknown specimens to perform direct genotyping of the beta-thalassemia specimens using HRM. The HRM-based genotyping of the unknown specimens showed 100% consistency with the sequencing result. CONCLUSIONS Targeting the mutational hot-spot, the HRM approach could be successfully applied for screening of beta-thalassemia carriers in Bangladesh as well as in other countries of South Asia and Southeast Asia. The approach could be a useful supplement of hematological and electrophortic indices in order to avoid false positive and false negative results.
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Affiliation(s)
- Md Tarikul Islam
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Suprovath Kumar Sarkar
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Nusrat Sultana
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Mst Noorjahan Begum
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Golam Sarower Bhuyan
- Infectious Diseases Laboratory, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Shezote Talukder
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - A K M Muraduzzaman
- Department of Virology, Institute of Epidemiology, Disease Control and Research, Mohakhali, Dhaka, Bangladesh
| | - Md Alauddin
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Mohammad Sazzadul Islam
- Infectious Diseases Laboratory, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Pritha Promita Biswas
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Aparna Biswas
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Syeda Kashfi Qadri
- Department of Paediatric Medicine, KK Women's and Children's Hospital, 100 Bukit Timah Road, Singapore, Singapore
| | - Tahmina Shirin
- Department of Virology, Institute of Epidemiology, Disease Control and Research, Mohakhali, Dhaka, Bangladesh
| | - Bilquis Banu
- Department of Biochemistry and Molecular Biology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Salma Sadya
- Department of Biochemistry and Molecular Biology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Manzoor Hussain
- Department of Biochemistry and Molecular Biology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Golam Sarwardi
- Department of Biochemistry and Molecular Biology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Waqar Ahmed Khan
- Department of Biochemistry and Molecular Biology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Mohammad Abdul Mannan
- Department of Neonatology, Bangabandhu Sheikh Mujib Medical University, Shahbag, Dhaka, Bangladesh
| | - Hossain Uddin Shekhar
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh
| | - Emran Kabir Chowdhury
- Department of Biochemistry and Molecular Biology, University of Dhaka, Dhaka, Bangladesh
| | - Abu Ashfaqur Sajib
- Department of Genetic Engineering & Biotechnology, University of Dhaka, Dhaka, Bangladesh
| | - Sharif Akhteruzzaman
- Department of Genetic Engineering & Biotechnology, University of Dhaka, Dhaka, Bangladesh
| | - Syed Saleheen Qadri
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh
| | - Firdausi Qadri
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh.,Department of Enteric and Respiratory Infectious Diseases, Infectious Diseases Division, International Centre for Diarrhoeal Disease Research, Bangladesh, Mohakhali, Dhaka, Bangladesh
| | - Kaiissar Mannoor
- Laboratory of Genetics and Genomics, Institute for Developing Science and Health Initiatives, Mohakhali, Dhaka, Bangladesh.
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Borgio JF, AbdulAzeez S, Al-Muslami AM, Naserullah ZA, Al-Jarrash S, Al-Suliman AM, Al-Madan MS, Al-Ali AK. KLF1 gene and borderline hemoglobin A 2 in Saudi population. Arch Med Sci 2018; 14:230-236. [PMID: 29379553 PMCID: PMC5778434 DOI: 10.5114/aoms.2018.72245] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/01/2017] [Accepted: 06/29/2017] [Indexed: 02/02/2023] Open
Abstract
INTRODUCTION Elevated HbA2 (hemoglobin A2) level is considered the most reliable hematological parameter for the detection of β-thalassemia carriers. However, some carriers are difficult to recognize because the level of HbA2 is not in the distinctive carrier range, i.e. 4.0-6.0%; instead, some carriers have HbA2 levels between normal and carrier levels, i.e. borderline HbA2 (HbA2 = 3.1-3.9%). Studies have shown that variations in the erythroid Krüppel-like factor (KLF1) gene lead to borderline HbA2 in β-thalassemia carriers from various populations. The incidence of borderline HbA2 in Saudis is high. MATERIAL AND METHODS To confirm the influence of variations in KLF1, HBA1, HBA2 and HBB genes for the reduction of the level of HbA2 in Saudi β-thalassemia carriers, we performed a direct sequence analysis of KLF1, HBA1, HBA2 and HBB genes from 212 healthy Saudis (88 subjects: HbA2 < 3; 72 subjects: HbA2 = 3.1 to 3.9; 52 subjects HbA2 > 4.3). RESULTS The presence of the borderline HbA2 level is not specific to any type of β-thalassemia variation or β+-thalassemia variations in Saudis. Two exonic (c.304T>C and c.544T>C) and two 3' untranslated region (3'UTR) (c.*296G>A and c.*277C>G) variations have been identified in the KLF1 gene for the first time from an Arab population. None of these four variations in KLF1 genes are significantly associated with the Saudis with borderline HbA2. α Globin genotype, -α23.7/α1α2, is found to be the most frequent (55.55%) among healthy Saudis with borderline HbA2 compared with the other groups (HbA2 < 3 = 20.45%; HbA2 > 4.3 = 13.51%). CONCLUSIONS Further studies are necessary to determine the influence of other factors on the presence of borderline HbA2 in 41.67% of Saudis.
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Affiliation(s)
- J. Francis Borgio
- Department of Genetic Research, Institute for Research and Medical Consultation (IRMC), University of Dammam, Dammam, Saudi Arabia
| | - Sayed AbdulAzeez
- Department of Genetic Research, Institute for Research and Medical Consultation (IRMC), University of Dammam, Dammam, Saudi Arabia
| | - Ahmed M. Al-Muslami
- Department of Genetic Research, Institute for Research and Medical Consultation (IRMC), University of Dammam, Dammam, Saudi Arabia
| | | | | | - Ahmed M. Al-Suliman
- Al-Omran Scientific Chair for Hematological Diseases Prevalent in the Al-Ahssa Area, King Faisal University, Al-Ahssa, Saudi Arabia
| | - Mohammed S. Al-Madan
- Department of Pediatrics, King Fahd Hospital of the University, Al-Khobar, Saudi Arabia
| | - Amein K. Al-Ali
- Department of Biochemistry, University of Dammam, Dammam, Saudi Arabia
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Borgio JF, Abdulazeez S, Almandil NB, Naserullah ZA, Al-Jarrash S, Al-Suliman AM, Elfakharay HI, Qaw FS, Alabdrabalnabi FI, Alkhalifah MA, Shakil Akhtar M, Qutub H, Al-Ali AK. The ‑α3.7 deletion in α‑globin genes increases the concentration of fetal hemoglobin and hemoglobin A2 in a Saudi Arabian population. Mol Med Rep 2017; 17:1879-1884. [PMID: 29138844 DOI: 10.3892/mmr.2017.8033] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 09/29/2017] [Indexed: 11/06/2022] Open
Abstract
The regions of Al‑Qatif and Al‑Ahssa in the Eastern Province of Saudi Arabia are known for their high prevalence of hemoglobinopathies, including β‑thalassemia and sickle cell anemia. Previously, the α‑gene deletion has been demonstrated as highly prevalent among populations residing in these two regions. The present study was conducted in order to investigate the implications of the α‑globin gene deletion on fetal hemoglobin (HbF) and hemoglobin α2 (HbA2) concentrations in patients with transfusion‑dependent β‑thalassemia. A total of 166 Saudi patients with transfusion‑dependent β‑thalassemia and 337 healthy Saudi patients were included in the study. The ‑α3.7, ‑α4.2, -‑FIL, -‑SEA, -‑MED and -‑(20.5) gene deletions were identified using multiplex α‑globin deletion polymerase chain reaction. The present study revealed that the ‑α3.7 gene deletion is the most prevalent (43.5%) in the Saudi populations that were analyzed and is characterized by the deletion of 3,804 base pairs. Numerous genotypes, namely ‑3.7α2/α1α2, ‑3.7α2/α1α12, ‑3.7α2/‑3.7α2, ‑3.7α2HphI/α1α2HphI, ‑3.7α2/α1‑4.2, ‑3.7α2/α1polyA‑1α2, ‑3.7α12/α1α12, ‑‑FIL/‑3.7α2 and ‑3.7α2/‑3.7α2Hb Villiers le Bel were also identified in the investigated population. Furthermore, a gradual increase in the concentration of HbF and HbA2 in patients with β‑thalassemia and the number of α‑gene deletions was demonstrated; whereas in healthy patients the level of HbA2 was demonstrated to decrease as the number of α‑gene deletions increased. Therefore, it can be concluded that the high HbF concentration in the present study is predominantly associated with other mutations associated with β‑thalassemia rather than α‑globin deletions. Furthermore, the results of the present study also revealed novel α‑gene deletion genotypes prevalent in the population studied, namely α1α2/α1α2HphI, α1α2HphI/α1α2HphI, α1α2/α1α2Hb Handsworth, ‑3.7α2HphI/α1α2HphI, ‑3.7α2/‑3.7α2Hb Villiers le Bel and ‑-MED/α1α2HphI.
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Affiliation(s)
- J Francis Borgio
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia
| | - Sayed Abdulazeez
- Department of Genetic Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia
| | - Noor B Almandil
- Department of Clinical Pharmacy Research, Institute for Research and Medical Consultation, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia
| | | | - Sana Al-Jarrash
- Dammam Maternity and Child Hospital, Dammam 32253, Saudi Arabia
| | - Ahmed M Al-Suliman
- Al‑Omran Scientific Chair for Hematological Diseases Prevalent in The Al‑Ahssa Area, King Faisal University, Al‑Ahssa 31982, Saudi Arabia
| | | | - Fuad S Qaw
- Department of Biochemistry, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia
| | | | | | - Mohammed Shakil Akhtar
- Department of Biochemistry, Imam Abdulrahman Bin Faisal University, Dammam 31441, Saudi Arabia
| | - Hatem Qutub
- King Fahd Hospital of The University, Al‑Khobar 34445, Saudi Arabia
| | - Amein K Al-Ali
- Al‑Omran Scientific Chair for Hematological Diseases Prevalent in The Al‑Ahssa Area, King Faisal University, Al‑Ahssa 31982, Saudi Arabia
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38
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Genetic variation of Krüppel-like factor 1 (KLF1) and fetal hemoglobin (HbF) levels in β 0-thalassemia/HbE disease. Int J Hematol 2017; 107:297-310. [PMID: 29067594 DOI: 10.1007/s12185-017-2357-3] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Revised: 10/09/2017] [Accepted: 10/10/2017] [Indexed: 12/21/2022]
Abstract
Heterogeneity of HbF levels in β0-thalassemia/HbE disease has been reported to be associated with variations in clinical manifestations of the disease, and several genetic-modifying factors beyond the β-globin gene cluster have been identified as HbF regulators. Down-regulation or heterozygous mutations of Krüppel-like factor 1 (KLF1) is associated with elevated HbF levels in non-thalassemia subjects. This study confirms that experimental down-regulation of KLF1 in β0-thalassemia/HbE-derived erythroblasts significantly increases HbF production (up to 52.3 ± 2.4%), albeit with slightly delayed erythroid terminal differentiation. KLF1 exome sequencing of 130 Thai β0-thalassemia/HbE patients without co-inheritance of α-thalassemia found six patients with KLF1 heterozygous mutations including rs2072596 (p.F182L; n = 5) and rs745347362 (p.P284L; n = 1) missense mutations. However, while these patients had high HbF levels (38.1 ± 7.5%), they were all associated with a severe clinical phenotype. These results suggest that while reduction of KLF1 expression in β0-thalassemia/HbE erythroblasts can increase HbF levels, it is not sufficient to alleviate the clinical phenotype.
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Keller J, Vege S, Horn T, Keller MA, Leger RM, Aeschlimann J, Lomas-Francis C, Westhoff CM. Novel mutations inKLF1encoding the In(Lu) phenotype reflect a diversity of clinical presentations. Transfusion 2017; 58:196-199. [DOI: 10.1111/trf.14378] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Revised: 09/01/2017] [Accepted: 09/06/2017] [Indexed: 12/01/2022]
Affiliation(s)
- Jessica Keller
- National Molecular Laboratory; American Red Cross Biomedical Services; Philadelphia Pennsylvania
| | - Sunitha Vege
- Laboratory of Immunohematology and Genomics; New York Blood Center; New York New York
| | - Trina Horn
- National Molecular Laboratory; American Red Cross Biomedical Services; Philadelphia Pennsylvania
| | - Margaret A. Keller
- National Molecular Laboratory; American Red Cross Biomedical Services; Philadelphia Pennsylvania
| | - Regina M. Leger
- American Red Cross Blood Services Southern California Region; Pomona California
| | - Judith Aeschlimann
- Laboratory of Immunohematology and Genomics; New York Blood Center; New York New York
| | | | - Connie M. Westhoff
- Laboratory of Immunohematology and Genomics; New York Blood Center; New York New York
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40
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Yu S, Chen Y, Lai K, Dewan RK, He Y. A Novel Variant with Positive Natural Selection Influenced Hb A 2 Levels in Chinese Individuals with β-Thalassemia. Hemoglobin 2017; 41:193-197. [PMID: 28747083 DOI: 10.1080/03630269.2017.1358177] [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: 10/19/2022]
Abstract
β-Thalassemia (β-thal) is the most common inherited hemolytic anemia worldwide. Elevated Hb A2 is a mark of β-thal carriers. The aim of this study was to identify the pathogenic variants associated with the Hb A2 levels. One thousand and thirty β-thal carriers were recruited for this study. Using positive natural expression quantitative trait loci (eQTL) analysis, a significant variant was selected. Genotyping for the rs231841 polymorphism was performed by the Sequenom MassARRAY IPLEX platform. All genetic association analyses were performed with the PLINK program. The linear regression analysis showed that rs231841 in the intron region of the potassium voltage-gated channel subfamily Q member 1 (KCNQ1) gene on chromosome 11p15 was significantly associated with Hb A2 levels. The presence of the C allele was associated with elevated Hb A2 levels. Our results suggest that rs231841 on the KCNQ1 gene with positive natural selection is related to Hb A2 levels in Chinese β-thal carriers, and KCNQ1 is probably associated with the expression of the β-like globin gene cluster.
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Affiliation(s)
- Shanjuan Yu
- a Department of Pediatrics , The First Affiliated Hospital of Guangxi Medical University , Nanning , Guangxi Province , People's Republic of China
| | - Yang Chen
- b School of Public Health, Guangxi Medical University , Nanning , Guangxi Province , People's Republic of China
| | - Ketong Lai
- c Guangxi Key Laboratory of Thalassemia Research , The First Affiliated Hospital of Guangxi Medical University , Nanning , Guangxi Province , People's Republic of China
| | - Roma Kajal Dewan
- a Department of Pediatrics , The First Affiliated Hospital of Guangxi Medical University , Nanning , Guangxi Province , People's Republic of China
| | - Yunyan He
- a Department of Pediatrics , The First Affiliated Hospital of Guangxi Medical University , Nanning , Guangxi Province , People's Republic of China
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41
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Satta S, Paglietti ME, Sollaino MC, Barella S, Moi P, Desogus MF, Demartis FR, Manunza L, Origa R. Changes in HbA2 and HbF in alpha thalassemia carriers with KLF1 mutation. Blood Cells Mol Dis 2017; 64:30-32. [DOI: 10.1016/j.bcmd.2017.03.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2016] [Revised: 03/16/2017] [Accepted: 03/17/2017] [Indexed: 12/29/2022]
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42
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Kawai M, Obara K, Onodera T, Enomoto T, Ogasawara K, Tsuneyama H, Uchikawa M, Inaba S. Mutations of theKLF1gene detected in Japanese with the In(Lu) phenotype. Transfusion 2017; 57:1072-1077. [DOI: 10.1111/trf.13990] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 11/08/2016] [Accepted: 11/30/2016] [Indexed: 11/29/2022]
Affiliation(s)
- Miho Kawai
- Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center; Saitama Japan
| | - Kumi Obara
- Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center; Saitama Japan
| | - Takayuki Onodera
- Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center; Saitama Japan
| | - Takayuki Enomoto
- Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center; Saitama Japan
| | | | - Hatsue Tsuneyama
- Japanese Red Cross Central Blood Institute; Tokyo Japan
- Japanese Red Cross Kanto-Koshinetsu Block Blood Center; Tokyo Japan
| | - Makoto Uchikawa
- Japanese Red Cross Kanto-Koshinetsu Block Blood Center; Tokyo Japan
| | - Shoichi Inaba
- Japanese Red Cross Kanto-Koshinetsu Block Saitama Blood Center; Saitama Japan
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43
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Sripichai O, Fucharoen S. Fetal hemoglobin regulation in β-thalassemia: heterogeneity, modifiers and therapeutic approaches. Expert Rev Hematol 2016; 9:1129-1137. [PMID: 27801605 DOI: 10.1080/17474086.2016.1255142] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Stress erythropoiesis induces fetal hemoglobin (HbF) expression in β-thalassemias, however the level of expression is highly variable. The last decade has seen dramatic advances in our understanding of the molecular regulators of HbF production and the genetic factors associated with HbF levels, leading to the promise of new methods of the clinical induction of HbF. Areas covered: This article will review the heterogeneity and genetic modifiers of HbF and HbF induction therapy in β-thalassemia. Expert commentary: One promising curative β-thalassemia therapy is to induce HbF synthesis in β-thalassemic erythrocytes to therapeutic levels before clinical symptom occurs. Further understanding of HbF level variation and regulation is needed in order to predict the response from HbF-inducing approaches.
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Affiliation(s)
- Orapan Sripichai
- a Thalassemia Research Center, Institute of Molecular Biosciences , Mahidol University , Nakhonpathom , Thailand
| | - Suthat Fucharoen
- a Thalassemia Research Center, Institute of Molecular Biosciences , Mahidol University , Nakhonpathom , Thailand
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44
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Turner A, Sasse J, Varadi A. Rapid detection of pathological mutations and deletions of the haemoglobin beta gene (HBB) by High Resolution Melting (HRM) analysis and Gene Ratio Analysis Copy Enumeration PCR (GRACE-PCR). BMC MEDICAL GENETICS 2016; 17:75. [PMID: 27756326 PMCID: PMC5070150 DOI: 10.1186/s12881-016-0334-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2016] [Accepted: 09/29/2016] [Indexed: 11/10/2022]
Abstract
OBJECTIVES Inherited disorders of haemoglobin are the world's most common genetic diseases, resulting in significant morbidity and mortality. The large number of mutations associated with the haemoglobin beta gene (HBB) makes gene scanning by High Resolution Melting (HRM) PCR an attractive diagnostic approach. However, existing HRM-PCR assays are not able to detect all common point mutations and have only a very limited ability to detect larger gene rearrangements. The aim of the current study was to develop a HBB assay, which can be used as a screening test in highly heterogeneous populations, for detection of both point mutations and larger gene rearrangements. METHODS The assay is based on a combination of conventional HRM-PCR and a novel Gene Ratio Analysis Copy Enumeration (GRACE) PCR method. HRM-PCR was extensively optimised, which included the use of an unlabelled probe and incorporation of universal bases into primers to prevent interference from common non-pathological polymorphisms. GRACE-PCR was employed to determine HBB gene copy numbers relative to a reference gene using melt curve analysis to detect rearrangements in the HBB gene. The performance of the assay was evaluated by analysing 410 samples. RESULTS A total of 44 distinct pathological genotypes were detected. In comparison with reference methods, the assay has a sensitivity of 100 % and a specificity of 98 %. CONCLUSION We have developed an assay that detects both point mutations and larger rearrangements of the HBB gene. This assay is quick, sensitive, specific and cost effective making it suitable as an initial screening test that can be used for highly heterogeneous cohorts.
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Affiliation(s)
- Andrew Turner
- Department of Pathology and Laboratory Medicine, Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates.
| | - Jurgen Sasse
- Department of Pathology and Laboratory Medicine, Sheikh Khalifa Medical City, Abu Dhabi, United Arab Emirates
| | - Aniko Varadi
- Department of Applied Sciences, Faculty of Health and Applied Sciences, University of the West of England, Bristol, UK
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45
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Breton A, Theodorou A, Aktuna S, Sonzogni L, Darling D, Chan L, Menzel S, van der Spek PJ, Swagemakers SMA, Grosveld F, Philipsen S, Thein SL. ASH1L (a histone methyltransferase protein) is a novel candidate globin gene regulator revealed by genetic study of an English family with beta-thalassaemia unlinked to the beta-globin locus. Br J Haematol 2016; 175:525-530. [PMID: 27434206 DOI: 10.1111/bjh.14256] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 06/06/2016] [Indexed: 01/14/2023]
Abstract
In 1993, we described an English family with beta-thalassaemia that was not linked to the beta-globin locus. Whole genome sequence analyses revealed potential causative mutations in 15 different genes, of which 4 were consistently and uniquely associated with the phenotype in all 7 affected family members, also confirmed by genetic linkage analysis. Of the 4 genes, which are present in a centromeric region of chromosome 1, ASH1L was proposed as causative through functional mRNA knock-down and chromatin-immunoprecipitation studies in human erythroid progenitor cells. Our data suggest a putative role for ASH1L (Trithorax protein) in the regulation of globin genes.
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Affiliation(s)
- Amandine Breton
- Molecular Haematology, Division of Cancer Studies, King's College London Faculty of Life Sciences and Medicine, London, SE5 9NU, UK
| | - Andria Theodorou
- Molecular Haematology, Division of Cancer Studies, King's College London Faculty of Life Sciences and Medicine, London, SE5 9NU, UK
| | - Suleyman Aktuna
- Molecular Haematology, Division of Cancer Studies, King's College London Faculty of Life Sciences and Medicine, London, SE5 9NU, UK
| | - Laura Sonzogni
- Molecular Haematology, Division of Cancer Studies, King's College London Faculty of Life Sciences and Medicine, London, SE5 9NU, UK
| | - David Darling
- Department of Haematological Medicine, King's College Hospital NHS Foundation Trust, London, SE5 9RS, UK
| | - Lucas Chan
- Department of Haematological Medicine, King's College Hospital NHS Foundation Trust, London, SE5 9RS, UK
| | - Stephan Menzel
- Molecular Haematology, Division of Cancer Studies, King's College London Faculty of Life Sciences and Medicine, London, SE5 9NU, UK
| | | | | | - Frank Grosveld
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands.,Netherlands Consortium for Systems Biology, Erasmus MC, Rotterdam, The Netherlands.,Centre for Biomedical Genetics, Erasmus MC, Rotterdam, The Netherlands
| | - Sjaak Philipsen
- Department of Cell Biology, Erasmus MC, Rotterdam, The Netherlands.,Netherlands Consortium for Systems Biology, Erasmus MC, Rotterdam, The Netherlands
| | - Swee Lay Thein
- Molecular Haematology, Division of Cancer Studies, King's College London Faculty of Life Sciences and Medicine, London, SE5 9NU, UK. .,Department of Haematological Medicine, King's College Hospital NHS Foundation Trust, London, SE5 9RS, UK.
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46
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Tepakhan W, Yamsri S, Sanchaisuriya K, Fucharoen G, Xu X, Fucharoen S. Nine known and five novel mutations in the erythroid transcription factor KLF1 gene and phenotypic expression of fetal hemoglobin in hemoglobin E disorder. Blood Cells Mol Dis 2016; 59:85-91. [DOI: 10.1016/j.bcmd.2016.04.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 04/24/2016] [Accepted: 04/24/2016] [Indexed: 01/26/2023]
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47
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Luo HY, Chui DHK. Diverse hematological phenotypes of β-thalassemia carriers. Ann N Y Acad Sci 2016; 1368:49-55. [PMID: 27123947 DOI: 10.1111/nyas.13056] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2016] [Revised: 03/03/2016] [Accepted: 03/07/2016] [Indexed: 01/19/2023]
Abstract
Most β-thalassemia carriers have mild anemia, low mean corpuscular volume and mean corpuscular hemoglobin, and elevated hemoglobin α2 (HbA2 ). However, there is considerable variability resulting from coinheritance with α- and/or δ-globin gene mutations, dominant inheritance of β-thalassemia mutations, highly unstable variant globin chains, large deletions removing part or all of the β-globin gene cluster, loss of heterozygosity of the β-globin gene cluster during development, or concomitant erythroid enzyme or membrane protein abnormalities. Recognition of the specific abnormality and correct diagnosis can allay anxiety and unnecessary investigation, help formulate treatment programs, and deliver appropriate genetic and family counseling.
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Affiliation(s)
- Hong-Yuan Luo
- Departments of Medicine, Pathology, and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts
| | - David H K Chui
- Departments of Medicine, Pathology, and Laboratory Medicine, Boston University School of Medicine, Boston, Massachusetts
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48
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Parmeggiani G, Gualandi F, Selvatici R, Rimessi P, Bigoni S, Taddei Masieri M, Dolcini B, Venturoli A, Cappabianca MP, Ferlini A, Ravani A. A Family with γ-Thalassemia and High Hb A2Levels. Hemoglobin 2016; 40:187-90. [DOI: 10.3109/03630269.2016.1148613] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
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49
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Krüppeling erythropoiesis: an unexpected broad spectrum of human red blood cell disorders due to KLF1 variants. Blood 2016; 127:1856-62. [PMID: 26903544 DOI: 10.1182/blood-2016-01-694331] [Citation(s) in RCA: 112] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 02/09/2016] [Indexed: 02/06/2023] Open
Abstract
Until recently our approach to analyzing human genetic diseases has been to accurately phenotype patients and sequence the genes known to be associated with those phenotypes; for example, in thalassemia, the globin loci are analyzed. Sequencing has become increasingly accessible, and thus a larger panel of genes can be analyzed and whole exome and/or whole genome sequencing can be used when no variants are found in the candidate genes. By using such approaches in patients with unexplained anemias, we have discovered that a broad range of hitherto unrelated human red cell disorders are caused by variants in KLF1, a master regulator of erythropoiesis, which were previously considered to be extremely rare causes of human genetic disease.
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Paglietti ME, Satta S, Sollaino MC, Barella S, Ventrella A, Desogus MF, Demartis FR, Manunza L, Origa R. The Problem of Borderline Hemoglobin A2 Levels in the Screening for β-Thalassemia Carriers in Sardinia. Acta Haematol 2016; 135:193-9. [PMID: 26794457 DOI: 10.1159/000442194] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2015] [Accepted: 11/04/2015] [Indexed: 01/08/2023]
Abstract
BACKGROUND The increase in HbA2 is the most important parameter for the identification of thalassemia carriers. However, in routine screening for hemoglobinopathies, some cases are difficult to classify because the level of HbA2 is not typically elevated. In this work, we report the results of a molecular investigation on a cohort of subjects with borderline HbA2. METHODS All subjects with a β-thalassemia carrier partner and a borderline percentage level of HbA2 were investigated for the presence of a pathological mutation in the β-globin gene. All negative subjects were screened for both the KLF1 mutation and the presence of ααα/ or αααα/ alleles. The subjects with reduced MCV and/or MCH were also screened for deletional and nondeletional α-globin gene defects. RESULTS Various β-globin mutations and KLF1 gene defects are the most common genetic determinants responsible for this phenotype in our population. CONCLUSION KLF1 mutations are important in a screening program for hemoglobinopathies. An increase in HbF in association with borderline HbA2 levels is a useful but not exclusive marker that suggests the investigation of this gene. On the basis of our findings, we are able to suggest the molecular procedure to use in a population characterized by a high prevalence of thalassemia carriers.
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Affiliation(s)
- Maria Elisabetta Paglietti
- Dipartimento di Sanitx00E0; Pubblica, Medicina Clinica e Molecolare, Universitx00E0; degli Studi di Cagliari, Ospedale Microcitemico, Cagliari, Italy
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