SPECTRUM OF BETA GLOBIN GENE MUTATIONS IN EGYPTIAN CHILDREN WITH β- THALASSEMIA

Background: The molecular defects resulting in β-thalassemia phenotype, in the Egyptian population show a clear heterogenic mutations pattern. PCR based techniques, including direct DNA sequencing are effective on the molecular detection and characterization of these mutations. The molecular characterization of β-thalassemia is absolutely necessary for carrier screening, for genetic counseling, and to offer prenatal diagnosis.The aim of the work: was to evaluate the different β-globin gene mutations in one hundred Egyptian children with β-thalassemia. Patients and Methods: One hundred of β-thalassemic Egyptian children, covering most Egyptian Governorates. All patients were subjected to meticulous history taking, clinical examinations, complete blood count, complete blood count, hemoglobin electrophoresis, serum ferritin and direct fluorescent DNA sequencing of β-globin gene to detect the frequency of different mutations in studied patients. Results: The most common mutations among patients were IVS I-110(G>A) 48%, IVS I-6(T>C) 40%, IVS I-1(G>A)19%,IVS I-5(G>C)10%, IVS II-848 (C>A) 9%, IVS II-745(C>G) 8%, IVS II-1(G>A) 7%, codon"Cd"39(C> T) 4%,-87(C>G) 3% and the rare mutations were: Cd37 (G>A), Cd8 (-AA), Cd29(-G), Cd5 (-CT), Cd6(-A), Cd8/9(+G), Cd 106/107(+G), Cd27(C>T), IVS II-16(G> C), Cd 28 (-C), Cap+1(A>C), -88(C>A), all of these rare mutations were present in 1%. There was considerable variation in phenotypic severity among patients resulting from interaction of different β° and β+mutations, 79(79%) patients were thalassemia major (TM) and 21(21%) were thassemia intermedia (TI), without genotype phenotype association. Conclusion: Direct DNA sequencing provides insights for the frequency of different mutations in β- thalassemic patients including rare and /or unknown ones.

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Detection of β and δ globin gene mutations by PCR and direct DNA sequencing in an individual with normal HbA2 β thalassemia

Pathology ◽

10.3109/00313029209063614 ◽

1992 ◽

Vol 24 (1) ◽

pp. 15-18

Author(s):

R.J. Trent ◽

S.L. Thein

Keyword(s):

Dna Sequencing ◽

Globin Gene ◽

Gene Mutations ◽

Direct Dna Sequencing

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The predominance of codon 39 (c>t) mutation of HBB gene in a portion of the Algerian population (Northeast Algeria)

Journal of Biological Research - Bollettino della Società Italiana di Biologia Sperimentale ◽

10.4081/jbr.2017.6407 ◽

2017 ◽

Vol 90 (1) ◽

Author(s):

Belhadi Kamilia ◽

Yahia Mouloud ◽

Gribaa Moez ◽

Bendaoud Fadhila ◽

Ben Charfeddine Ilhem ◽

...

Keyword(s):

Globin Gene ◽

Gene Mutations ◽

University Hospital ◽

Beta Globin ◽

Frequent Mutation ◽

Direct Dna Sequencing ◽

Beta Globin Gene ◽

Rare Mutations ◽

Algerian Population ◽

Geographical Regions

This study was planned to determine the frequency of β-thalassemia mutations in Batna region (Northeast Algeria). Nineteen blood samples of clinically thalassemic children patients were collected from Department of Pediatrics, University Hospital of Batna. We carried out the molecular genetics of beta globin gene by the method of minisequencing using Snapshot™ kit (Applied Biosystems) in search of the four most common HBB genetic variants including three β-thalassemia mutations: codon 39(C>T) (HBB: c.118C>T), IVSI-110(G>A) (HBB: c.93-21G>A), and IVSI-1-2(T>G) (HBB: c.92+2T>G), as well as the hemoglobin S variant (HBB: c.20A>T). We used direct DNA sequencing to detect the rare mutations of beta-globin gene. We have revealed the presence of four different β-globin gene mutations responsible for β-thalassemia in Batna region. According to our results, the nonsense mutation at codon 39 (C>T) is the most frequent mutation type in our province, the same as other geographical regions of Algeria. It is followed by codon 54(-T), detected in a second Algerian family (the proband was homozygote), and the first association of Hb Knossos: codon 27 (G>T) allele with codon 39 (C>T) in the Algerian population. Here we reportws also the association of codon 39(C>T) with IVS-I-110 (G>A). Our preliminary results show the predominance of codon 39 (c>t) mutation of HBB gene in Batna region.

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Current Perspective of Beta Thalassemia and Its Treatment Strategies

10.20944/preprints201907.0277.v1 ◽

2019 ◽

Author(s):

Shaukat Ali ◽

Shumaila Mumtaz ◽

Hafiz Abdullah Shakir ◽

Hafiz Muhammad Tahir ◽

Tafail Akbar Mughal

Keyword(s):

Genetic Testing ◽

Blood Transfusion ◽

Dna Analysis ◽

Complete Blood Count ◽

Globin Gene ◽

Thalassemia Major ◽

Beta Thalassemia ◽

Beta Globin ◽

Hematopoietic Stem ◽

Thalassemia Minor

Thalassemia is genetic blood disease cause by absence or decrease of one or more of the globin chain synthesis. Beta thalassemia is characterized by one or more mutations in beta globin gene. Absence or reduced amount the of beta globin chains cause ineffective erythropoiesis which leads to anemia. Beta thalassemia has been further divided into three main forms: Thalassemia minor/silent carrier, major and intermedia. More severe form is thalassemia major in which patients depend upon blood transfusion for survival and high level of iron occur as a consequence of consistent blood transfusion. Over loaded iron invokes the synthesis of reactive oxygen species that are toxic in redundancy and triggering the impairment to vascular, endocrine and hepatic system. Thalassemia can be diagnosed and detected through various laboratory tests such as blood smear, prenatal testing (genetic testing of amniotic fluid), DNA analysis (genetic testing) and complete blood count. Treatment of thalassemia intermedia is symptomatic but it can also be managed by splenectomy and folic supplementation. While thalassemia major can be treated by transplantation of bone marrow, regular transfusion of blood and iron chelation treatment, stimulation of fetal hemoglobin production, hematopoietic stem cell transplantation and gene therapy.

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Identification of a new β-thalassaemia variant Term CD+32(HBB: c.32A>C) in two Chinese families

Journal of Clinical Pathology ◽

10.1136/jclinpath-2020-206426 ◽

2020 ◽

Vol 73 (9) ◽

pp. 593-596

Author(s):

Jianlong Zhuang ◽

Yu Zheng ◽

Yuanbai Wang ◽

Qianmei Zhuang ◽

Yuying Jiang ◽

...

Keyword(s):

Dna Sequencing ◽

Elevated Level ◽

Globin Gene ◽

Novel Mutations ◽

Fujian Province ◽

Chinese Families ◽

Rare Mutation ◽

Direct Dna Sequencing ◽

Her Family ◽

Blood Disorder

Aimsβ-Thalassaemia is an inherited blood disorder caused by mutations in the β-globin gene cluster. Molecular characterisation of β-thalassaemia is essential for its diagnosis and management. More and more rare and novel mutations have been reported.MethodsTwo Chinese families with β-thalassaemia from Fujian Province were recruited in this study. The phenotypes of the probands were confirmed through haematological analysis. Routine molecular analysis of thalassaemia was employed to identify the common mutations of thalassaemia. The rare and novel mutations were detected by direct DNA sequencing.ResultsIn family 1, the proband, a Chinese woman aged 31 years, showed elevated level of haemoglobin A2 (HbA2). No common mutations associated with β-thalassaemia were detected, whereas a rare mutation Term CD+32(HBB: c.32A>C) was identified through DNA sequencing. Subsequent investigation of the β-thalassaemia mutation in her family showed that her mother, her brother as well as her nephew also carried this mutation. In addition, both the proband’s husband and her son carrying the rare --THAI mutation exhibited decreased levels of MCH, MCH and HbA2. In family 2, the proband, a child aged 1 year, showed elevated level of HbA2, but had no common mutations of β-thalassaemia. The proband was identified carrying the mutation Term CD+32(HBB: c.32A>C), which was inherited from his mother.ConclusionsIn this study, we first report a rare β-thalassaemia mutation in Fujian Province, Southeast China. Moreover, our study also identified this rare mutation in humans. This finding has helped broaden the spectrum of β-thalassaemia mutations in our region and suggested that this rare mutation may be more prevalent in the Chinese population.

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BETA-GLOBIN GENE MUTATIONS IN TURKISH CHILDREN WITH BETA-THALASSEMIA: RESULTS FROM A SINGLE CENTER STUDY

Mediterranean Journal of Hematology and Infectious Diseases ◽

10.4084/mjhid.2013.055 ◽

2013 ◽

Vol 5 (1) ◽

pp. e2013055 ◽

Cited By ~ 13

Author(s):

Ali Fettah ◽

Cengiz Bayram ◽

Nese Yarali ◽

Pamir Isik ◽

Abdurrahman Kara ◽

...

Keyword(s):

Globin Gene ◽

Gene Mutations ◽

Thalassemia Major ◽

Compound Heterozygous Mutation ◽

Heterozygous Mutation ◽

Compound Heterozygous ◽

Homozygous Mutation ◽

Thalassemia Intermedia ◽

Turkish Children ◽

Tertiary Center

Introduction: The beta thalassemias are common genetic disorders in Turkey and in this retrospective study our aim was to evaluate β-globin chain mutations and the phenotypic severity of β-thalassemia patients followed-up in our hospital, a tertiary center which serves patients from all regions of Turkey. Materials and Methods: 106 pediatric patients were analysed for β-globin gene mutations by using DNA analysis. Patients were classified as having β-thalassemia major or β-thalassemia intermedia based on age at diagnosis, transfusion frequency and lowest hemoglobin concentration in between transfusions. Results: There were 106 patients (52.8% female and 47.2% male) with a mean age of 11.2±5 years (1.6 – 22.3 years). Eighty-four (79.2%) patients had β-thalassemia major, whereas the remaining 22 patients (20.8%) were identified as having β-thalassemia intermedia. Overall, 18 different mutations were detected on 212 alleles. The most frequently encountered mutation was IVS I.110 (G>A) (35.3%), followed by Codon 8 del-AA (10.4%), IVS II.1 (G>A) (8%), IVS I.1 (G>A) (7.5%), Codon 39 (C>T) (7.1%) and Codon 5 (-CT) (6.6%), which made up 79.4% of observed mutations. According to present results, IVS I.110 (G>AA) was the most frequent mutation observed in this study, as in other results from Turkey. Evaluation of β-thalassemia mutations in 106 patients with 212 alleles, revealed the presence of homozygous mutation in 85 patients (80.2%) and compound heterozygous mutation in 21 patients (19.8%). The mutations detected in patients with homozygous mutation were IVS I.110 (G>A) (38.8%), Codon 8 del –AA (11.8%), IVS II.1 (G>A) (8.2%) and IVS I.1 (G>A) (8.2%). Observed mutations in the compound heterozygotes were Codon 39 (C>T)/Codon 41-42 (-CTTT) (14.3%), IVS I.110 (G>A)/Codon 39(C>T) (14.3%), IVS I.110 (G>A)/Codon 44(-C) (14.3%), and IVS II.745 (C>G)/ 5’UTR + 22 (G>A) (9.5%). Conclusion: Our hospital is a tertiary referral center that provides care to patients from all over the country, and thus the distribution of mutations observed in the current study is significant in term of representing that of the country as a whole.

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Molecular Characterization of β- and α-Globin Gene Mutations in Individuals with Borderline Hb A2 Levels

Hemoglobin ◽

10.1080/03630269.2020.1826327 ◽

2020 ◽

Vol 44 (5) ◽

pp. 349-353

Author(s):

Surada Satthakarn ◽

Sitthichai Panyasai ◽

Sakorn Pornprasert

Keyword(s):

Molecular Characterization ◽

Globin Gene ◽

Gene Mutations

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Butyrylcholinesterase (BCHE) Genotyping for Post-Succinylcholine Apnea in an Australian Population

Clinical Chemistry ◽

10.1373/49.8.1297 ◽

2003 ◽

Vol 49 (8) ◽

pp. 1297-1308 ◽

Cited By ~ 53

Author(s):

Tina Yen ◽

Brian N Nightingale ◽

Jennifer C Burns ◽

David R Sullivan ◽

Peter M Stewart

Keyword(s):

Dna Sequencing ◽

Gene Mutations ◽

University Teaching ◽

Sequencing Analysis ◽

Direct Dna Sequencing ◽

Bche Activity ◽

Mutation Screen ◽

Sequencing Studies ◽

Dna Sequencing Analysis ◽

K Variant

Abstract Background: Measurement of plasma butyrylcholinesterase (BChE) activity and inhibitor-based phenotyping are standard methods for identifying patients who experience post-succinylcholine (SC) apnea attributable to inherited variants of the BChE enzyme. Our aim was to develop PCR-based assays for BCHE mutation detection and implement them for routine diagnostic use at a university teaching hospital. Methods: Between 1999 and 2002, we genotyped 65 patients referred after prolonged post-SC apnea. Five BCHE gene mutations were analyzed. Competitive oligo-priming (COP)-PCR was used for flu-1, flu-2, and K-variant and direct DNA sequencing analysis for dibucaine and sil-1 mutations. Additional DNA sequencing of BCHE coding regions was provided when the five-mutation screen was negative or mutation findings were inconsistent with enzyme activity. Results: Genotyping identified 52 patients with primary hypocholinesterasemia attributable to BCHE mutations, and in 44 individuals the abnormalities were detected by the five-mutation screen (detection rate, 85%). Additional sequencing studies revealed mutations in eight other patients, including five with novel mutations. The most common genotype abnormality was compound homozygous dibucaine and homozygous K-variant mutations. No simple homozygotes were found. Of the remaining 13 patients, 3 had normal BChE activity and gene, and 10 were diagnosed with hypocholinesterasemia unrelated to BCHE gene abnormalities. Conclusion: A five-mutation screen for investigation of post-SC apnea identified BCHE gene abnormalities for 80% of a referral population. Six new BCHE mutations were identified by sequencing studies of 16 additional patients.

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Frequency of hereditary hemochromatosis gene mutations and their effects on iron overload among beta thalassemia patients of Chennai residents

AIMS Molecular Science ◽

10.3934/molsci.2021018 ◽

2021 ◽

Vol 8 (4) ◽

pp. 233-247

Author(s):

Bhuvana Selvaraj ◽

◽

Sangeetha Soundararajan ◽

Shettu Narayanasamy ◽

Ganesan Subramanian ◽

...

Keyword(s):

Iron Overload ◽

Iron Status ◽

Globin Gene ◽

Hereditary Hemochromatosis ◽

Gene Mutations ◽

Autosomal Recessive Disorder ◽

Thalassemia Major ◽

Organ Damage ◽

Beta Thalassemia ◽

Hemochromatosis Gene

<abstract> Hereditary Hemochromatosis (HH) is an autosomal recessive disorder of iron metabolism associated with <italic>HFE</italic> gene mutations, characterized by increased iron absorption and accumulation leading to multi-organ damage caused by iron overload toxicity. Beta thalassemia is caused by a mutation in the human beta globin gene. Imbalanced production of globin chain results in beta thalassemia, where the unpaired alpha chains precipitates in red cell precursors leading to ineffective erythropoiesis and reduced RBC survival. Both HH and beta thalassemia condition results in rapid accumulation of iron lead to iron overload in tissues and organs. The study aims to analyze the frequency of <italic>HFE</italic> variants among beta thalassemia cases and their effect on iron overload. The frequency of three <italic>HFE</italic> variants C282Y, H63D, S65C was analyzed by PCR RFLP method among Beta Thalassemia Trait (BTT) (n = 203), Beta Thalassemia Major (BTM) (n = 19) and age and sex-matched control samples (n = 200). The present study furnished allele frequency of H63D variant in BTT, BTM and controls 8.13, 15.8 and 6% respectively. Ten out of 33 heterozygous H63D variants exhibited iron overload with higher ferritin levels indicating <italic>HFE</italic> variant might aggravate the absorption of iron. The C282Y variant was present in heterozygous state in 1 case among beta thalassemia carriers. The C282Y variant was absent among BTM and control cases. S65C <italic>HFE</italic> variant was absent in the present study. Iron overload was completely absent in the control cases among all three <italic>HFE</italic> genotypes. Hence it is inferred from the present investigation, analysis of <italic>HFE</italic> genes and iron status will remarkably help to reason out the probable reason behind the iron status and support in proper management of beta thalassemia cases. </abstract>

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Genotype-phenotype correlation of HbH disease in northern Iraq

BMC Medical Genetics ◽

10.1186/s12881-020-01141-8 ◽

2020 ◽

Vol 21 (1) ◽

Author(s):

Rawand P. Shamoon ◽

Ahmed K. Yassin ◽

Ranan K. Polus ◽

Mohamad D. Ali

Keyword(s):

Globin Gene ◽

Gene Mutations ◽

Globin Genes ◽

Phenotype Correlation ◽

Deletion Mutations ◽

Northern Iraq ◽

Screening And Prevention ◽

First Time ◽

Hbh Disease

Abstract Background HbH disease results from dysfunction of three, less commonly two, α-globin genes through various combinations of deletion and non-deletion mutations. Characterization of the mutations and the underlying genotypes is fundamental for proper screening and prevention of thalassaemia in any region. The aim of this study was to explore the genetic arrangements of HbH disease and to correlate the genotypes with the clinical phenotypes. Methods A total of 44 HbH disease patients were enrolled in this study. They were clinically and haematologically assessed. The patients were tested for 21 common α-globin gene mutations using multiplex PCR and reverse hybridization. According to the genotype, the patients were categorized into two separate sub-groups, deletion and non-deletion types HbH disease. Results Within the studied HbH disease patients, eight different α-globin gene mutations were detected in nine different genetic arrangements. The --MED and -α3.7 deletions were the two most frequently encountered mutations (37.5 and 35.2% respectively). Patients with deletion genotypes constituted 70.4%. The most common detected genotype was --MED/−α3.7 (59.1%), followed by αpoly-A1α/αpoly-A1α (13.6%). For the first time, coinheritance of two relatively mild mutations (−α3.7/ααAdana) was unpredictably detected in a 1.5 year-old child with Hb of 7.1 g/dL. Conclusion The HbH disease patients’ clinical characteristics were variable with no ample difference between the deletion and non-deletion types. These results can be of benefit for the screening and management of thalassaemia in this region.

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