scholarly journals Mutation in thalassemia syndrome and clinical manifestation

2020 ◽  
Vol 6 (2) ◽  
pp. e29-e29
Author(s):  
Ahmad Tamaddoni ◽  
Leila Gharehdaghly ◽  
Mohammad Bahadoram
Keyword(s):  
Blood Transfusion ◽  
Molecular Basis ◽  
Globin Gene ◽  
Clinical Severity ◽  
Clinical Aspects ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Dot Blot ◽  
Mazandaran Province ◽  
Beta Globin Gene

Introduction: Thalassemia intermedia is a term used to define a group of patients with β thalassemia in whom the clinical severity of the disease is somewhere between the mild symptoms of the β thalassemia trait and the severe manifestations of β thalassemia major. Thalassemia intermedia shows considerable heterogeneity in phenotype and molecular basis. Objectives: The aim of this study was to identify the common mutations of beta globin gene and the relationship between genotypes and phenotypes in thalassemia intermedia patients in Mazandaran province, in the north of Iran. Patients and Methods: Fifty unrelated thalassemia intermedia patients, based on clinical and hematological characteristics including age of diagnosis, age of first blood transfusion, history of blood transfusion, mean corpuscular volume (MCV), mean cell hemoglobin (MCH), hemoglobin values, and liver and spleen status were selected. DNA of peripheral blood was extracted and common mutations in beta globin gene were analyzed by reverse dot blot (RDB) method. Results: Our study showed that 30 patients (60%) had blood transfusion. There was no obvious hepatomegaly in any of the subjects, however 40 patients (80%) showed splenomegaly among which 34 cases (68%) underwent splenectomy. Mutations analysis indicated that HBB:c.315+1G>A [IVS II-1 (G>A)] mutation was the dominant mutation and has been widely associated with the phenotypic manifestations of thalassemia intermedia patients. Conclusion: It is important to comprehend the molecular basis of thalassemia intermedia and the association between genotype and phenotype in different ethnic groups. Therefore a careful evaluation of genetic, molecular, hematological and clinical aspects is necessary to differentiate thalassemia intermedia in patients at presentation.

scholarly journals Molecular characterization of beta-thalassemia intermedia in patients of Italian descent and identification of three novel beta-thalassemia mutations

Blood ◽  
1991 ◽  
Vol 77 (6) ◽  
pp. 1342-1347 ◽  
Author(s):  
S Murru ◽  
G Loudianos ◽  
M Deiana ◽  
C Camaschella ◽  
GV Sciarratta ◽  
...  
Keyword(s):  
Blot Analysis ◽  
Globin Gene ◽  
Beta Thalassemia ◽  
Italian Population ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Dot Blot ◽  
Beta Globin Gene ◽  
Dot Blot Analysis ◽  
Thalassemia Mutation

Abstract In this study, we have defined by dot-blot analysis with allelic specific oligonucleotide probes or direct sequencing on amplified DNA the beta-thalassemia mutations in a large group of patients (23) of Italian descent with thalassemia intermedia. These patients had one parent with either the silent beta-thalassemia carrier phenotype or borderline-normal hemoglobin A2 (HbA2) levels (2.5% to 3.5%). Nearly all were genetic compounds for a severe beta-thalassemia mutation and a beta-thalassemia mutation associated with high residual output of beta- globin chains (beta + intervening sequence [IVS]-I-nt6, beta -87, beta - 101), indicating that inheritance of a mild beta-thalassemia allele, even in a single dose, is the most common molecular mechanism producing thalassemia intermedia in the Italian population. In three cases, in whom we failed to define by dot-blot analysis the mutations, we sequenced the beta + globin gene and found three novel beta-thalassemia mutations, which are certainly very rare because they have been hitherto detected solely in a single patient. These mutations consist of: (1) a T-A substitution at position 2 of IVS-I, in a patient compound heterozygote for this mutation and the -87 promoter mutation; (2) a G-C substitution at position 844 of IVS-II, in a patient heterozygous for this mutation who showed normal sequences at the in trans beta-globin gene (The reason for the presence of clinical manifestations in a beta-thalassemia heterozygote has not been defined.); and (3) a deletion of one nucleotide (-T) at codon 126, resulting in a frameshift and readthrough of the 5′ untranslated region and most likely producing an elongated Hb molecule of 156 amino acid residues, in a patient heterozygous for this mutation with normal beta- globin gene sequences at the other locus.

scholarly journals Molecular characterization of beta-thalassemia intermedia in patients of Italian descent and identification of three novel beta-thalassemia mutations

Blood ◽  
1991 ◽  
Vol 77 (6) ◽  
pp. 1342-1347 ◽  
Author(s):  
S Murru ◽  
G Loudianos ◽  
M Deiana ◽  
C Camaschella ◽  
GV Sciarratta ◽  
...  
Keyword(s):  
Blot Analysis ◽  
Globin Gene ◽  
Beta Thalassemia ◽  
Italian Population ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Dot Blot ◽  
Beta Globin Gene ◽  
Dot Blot Analysis ◽  
Thalassemia Mutation

In this study, we have defined by dot-blot analysis with allelic specific oligonucleotide probes or direct sequencing on amplified DNA the beta-thalassemia mutations in a large group of patients (23) of Italian descent with thalassemia intermedia. These patients had one parent with either the silent beta-thalassemia carrier phenotype or borderline-normal hemoglobin A2 (HbA2) levels (2.5% to 3.5%). Nearly all were genetic compounds for a severe beta-thalassemia mutation and a beta-thalassemia mutation associated with high residual output of beta- globin chains (beta + intervening sequence [IVS]-I-nt6, beta -87, beta - 101), indicating that inheritance of a mild beta-thalassemia allele, even in a single dose, is the most common molecular mechanism producing thalassemia intermedia in the Italian population. In three cases, in whom we failed to define by dot-blot analysis the mutations, we sequenced the beta + globin gene and found three novel beta-thalassemia mutations, which are certainly very rare because they have been hitherto detected solely in a single patient. These mutations consist of: (1) a T-A substitution at position 2 of IVS-I, in a patient compound heterozygote for this mutation and the -87 promoter mutation; (2) a G-C substitution at position 844 of IVS-II, in a patient heterozygous for this mutation who showed normal sequences at the in trans beta-globin gene (The reason for the presence of clinical manifestations in a beta-thalassemia heterozygote has not been defined.); and (3) a deletion of one nucleotide (-T) at codon 126, resulting in a frameshift and readthrough of the 5′ untranslated region and most likely producing an elongated Hb molecule of 156 amino acid residues, in a patient heterozygous for this mutation with normal beta- globin gene sequences at the other locus.

scholarly journals Molecular analysis of beta zero-thalassemia intermedia in Sardinia

Blood ◽  
1989 ◽  
Vol 74 (2) ◽  
pp. 823-827 ◽  
Author(s):  
R Galanello ◽  
E Dessi ◽  
MA Melis ◽  
M Addis ◽  
MA Sanna ◽  
...  
Keyword(s):  
Nonsense Mutation ◽  
Frameshift Mutation ◽  
Globin Gene ◽  
Thalassemia Major ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Mild Phenotype ◽  
Beta Globin Gene ◽  
Alpha Thalassemia

Abstract In this study we have carried out alpha- and beta-globin gene analysis and defined the beta-globin gene polymorphisms in a group of patients with thalassemia intermedia of Sardinian descent. A group of patients (109) with thalassemia major of the same origin served as control. Characterization of the beta-thalassemia mutation showed either a frameshift mutation at codon 6 or a codon 39 nonsense mutation. We found that homozygotes for the frameshift mutation at codon 6 or compound heterozygotes for this mutation and for the codon 39 nonsense mutation develop thalassemia intermedia more frequently than thalassemia major. The frameshift mutation at codon 6 was associated with haplotype IX that contains the C-T change at position -158 5′ to the G gamma globin gene implicated in high gamma chain production and thus the mild phenotype. In patients' homozygotes for codon 39 nonsense mutation, those with thalassemia intermedia more frequently had the two- gene deletion form of alpha-thalassemia, or functional loss of the alpha 2 gene as compared with those with thalassemia major. In a few siblings with thalassemia major and intermedia, the thalassemia intermedia syndrome correlated with the presence of the -alpha/-alpha genotype. No cause for the mild phenotype was detected in the majority of patients who had not inherited either haplotype IX or alpha- thalassemia.

A C----T substitution at nt--101 in a conserved DNA sequence of the promotor region of the beta-globin gene is associated with “silent” beta-thalassemia

Blood ◽  
1989 ◽  
Vol 73 (6) ◽  
pp. 1705-1711 ◽  
Author(s):  
JM Gonzalez-Redondo ◽  
TA Stoming ◽  
A Kutlar ◽  
F Kutlar ◽  
KD Lanclos ◽  
...  
Keyword(s):  
Globin Gene ◽  
Beta Thalassemia ◽  
Nucleotide Position ◽  
Beta Globin ◽  
Dot Blot ◽  
Sequence Analyses ◽  
Beta Globin Gene ◽  
Chain Synthesis ◽  
Thalassemia Mutation

Sequence analyses and dot-blot analyses with synthetic oligonucleotide probes have identified eight individuals in three Turkish families and one Bulgarian family with one chromosome having a C----T mutation at nucleotide position--101 relative to the Cap site of the beta-globin gene. This nucleotide is part of one of the conserved blocks of nucleotides within the promoter region; in vitro expression analyses with the chloramphenicol acetyltransferase system showed that this substitution will decrease the effectiveness of transcription. Five subjects had a thalassemia intermedia due to the additional presence of a known classical high hemoglobin (Hb) A2 beta-thalassemia mutation on the second chromosome; their hematologic condition was relatively mild. The three persons with a heterozygosity for the--101 C----T mutation had normal hematologic data without microcytosis but with high-normal levels of Hb A2 and a mild imbalance in chain synthesis. The newly discovered mutation is considered one of the silent types of beta- thalassemia. It is relatively rare because it was absent among several hundred normal and beta-thalassemia chromosomes.

scholarly journals Phenotypes of Hb Okayama Mutation

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4898-4898
Author(s):  
Rudra Ray ◽  
Ankita Biswas ◽  
Sunistha Bhattacharjee ◽  
Maitreyee Bhattacharyya
Keyword(s):  
Blood Transfusion ◽  
Gene Mutation ◽  
Globin Gene ◽  
Silent Mutation ◽  
Pcr Analysis ◽  
Heterozygous Mutation ◽  
Compound Heterozygous ◽  
Heterozygous State ◽  
Beta Globin ◽  
Beta Globin Gene

Abstract Introduction: Since its first detection in the year of 1983 very little has been reported about Hb Okayama mutation. Hb Okayama, reported as a silent mutation (Globin Gene Server Hb Var ID: 220, dbSNP rs713040), happened to be detected in the process of HPLC analysis for the measurement of HbA1c in Japanese diabetic patient [1,2,3]. Till date only few Hb Okayama has been reported from Japanese and Austrian ethnicity [2,3,4]. Its phenotypes and co-inheritance with other beta globin gene mutation is not yet known. In this study we report phenotypes of Hb Okayama in heterozygous as well as compound heterozygous state when it is co-existing with a common beta globin gene mutation. To the best of our knowledge no such study has been reported in world literature. Methodology: Two groups of patients- beta carriers requiring blood transfusion; and patients with low MCV, MCH but normal in HPLC were further investigated by molecular analysis. ARMS PCR analysis for beta globin gene mutation detection, GAP PCR for alpha deletion and triplication analysis and DNA sequencing (ABI 3500 Genetic Analyzer) to identify rare beta mutations were carried out. Result: Among around 300 patients subjected to molecular investigation over last three years there were 118 cases of thalassaemia trait (by HPLC and confirmed to carry a heterozygous common beta mutations by ARMS PCR analysis), but were requiring blood transfusion or behaving like intermedia. They were subjected to alpha globin gene triplication analysis by GAP PCR. There were 84 cases found to carry absence of alpha triplication with heterozygous beta mutation. Beta globin gene sequencing analysis of these 84 patients revealed that there were 4 patients carrying Okayama heterozygous mutation [ Figure 1, Figure 2 ] along with a common heterozygous beta gene mutation ( IVS 1-5 G>C mutation). HPLC report of these patients carrying Hb Okayama along with IVS 1-5 mutations in compound heterozygous state showed increased HbA2 values like that of beta trait [Table 1 ]. Another group of patients with low MCV, MCH but Normal in HPLC were subjected to alpha deletion analysis after ruling out low Ferritin level. There were 72 patients showing absence of alpha deletion by GAP PCR analysis and carried low MCV, MCH value with Normal HPLC parameters were also subjected to beta globin gene sequencing which revealed the presence of Hb Okayama mutation among two patients in heterozygous state [Figure- 1, Figure 2], who had HbA2 values in normal or border line range with low MCV, MCH levels [Table-2]. Discussion: HbA2 measurement is used as the marker for screening of beta trait. Silent beta-thalassaemia carriers represent normal HbA2 level which makes their identification difficult. Okayama mutation or Hb Okayama is known to be a silent mutation [1-4] with normal HPLC. Hb Okayama is structural beta variant with a change of amino acid ( His > Gln) at Codon 2 (CD 2). Change in the nucleotide sequence at 70603 position from T to A or C (CAT>CAA or CAG) of beta globin gene (NG_000007.3) causes this mutation. The phenotypic associations of Hb Okayama in thalassaemia have very little been known till date. There has been report of very high expression of HbF(70%) value in HPLC resulting from compound heterozygous mutations one of which being silent (Cap+1) [ 5] ; where as there are also reports where the phenotypes of compound heterozygous including a silent mutation showing normal HPLC parameters [ 6 ]. However, in those studies no information about the clinical history and blood transfusion is described. In this study Hb Okayama heterozygous co-inheriting with IVS1-5(G>C) heterozygous mutation showed beta trait like HPLC parameters though all the patients carrying these compound heterozygous mutations required blood transfusion. The silent feature of Hb Okayama was evident in the case of the patients carrying only Hb Okayama mutation who showed absolutely normal HPLC parameters with low MCV, MCH and none of them requiring blood transfusion. Conclusion: Beta globin gene expression analysis to understand the association of Hb Okayama mutation in heterozygous and compound heterozygous states will enable to explain the mechanism of its phenotypes. How this mutation interferes with the expression of HbF or switching of delta globin gene is also to be understood as the HbF levels in HPLC was found to be like beta traits in this study. Disclosures No relevant conflicts of interest to declare.

scholarly journals Molecular analysis of beta zero-thalassemia intermedia in Sardinia

Blood ◽  
1989 ◽  
Vol 74 (2) ◽  
pp. 823-827 ◽  
Author(s):  
R Galanello ◽  
E Dessi ◽  
MA Melis ◽  
M Addis ◽  
MA Sanna ◽  
...  
Keyword(s):  
Nonsense Mutation ◽  
Frameshift Mutation ◽  
Globin Gene ◽  
Thalassemia Major ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Mild Phenotype ◽  
Beta Globin Gene ◽  
Alpha Thalassemia

In this study we have carried out alpha- and beta-globin gene analysis and defined the beta-globin gene polymorphisms in a group of patients with thalassemia intermedia of Sardinian descent. A group of patients (109) with thalassemia major of the same origin served as control. Characterization of the beta-thalassemia mutation showed either a frameshift mutation at codon 6 or a codon 39 nonsense mutation. We found that homozygotes for the frameshift mutation at codon 6 or compound heterozygotes for this mutation and for the codon 39 nonsense mutation develop thalassemia intermedia more frequently than thalassemia major. The frameshift mutation at codon 6 was associated with haplotype IX that contains the C-T change at position -158 5′ to the G gamma globin gene implicated in high gamma chain production and thus the mild phenotype. In patients' homozygotes for codon 39 nonsense mutation, those with thalassemia intermedia more frequently had the two- gene deletion form of alpha-thalassemia, or functional loss of the alpha 2 gene as compared with those with thalassemia major. In a few siblings with thalassemia major and intermedia, the thalassemia intermedia syndrome correlated with the presence of the -alpha/-alpha genotype. No cause for the mild phenotype was detected in the majority of patients who had not inherited either haplotype IX or alpha- thalassemia.

Severe Thalassemia Intermedia Resulting From Coinheritance of IVSI-110 G>A Beta Gene Mutation and Duplication of Alpha-Globin Gene Cluster in Homozygosis.

Blood ◽  
2009 ◽  
Vol 114 (22) ◽  
pp. 2011-2011 ◽  
Author(s):  
Chiara Refaldi ◽  
Wilma Barcellini ◽  
Elena Cassinerio ◽  
Giovanna Graziadei ◽  
Maria Domenica Cappellini
Keyword(s):  
Gene Cluster ◽  
Molecular Mechanisms ◽  
Globin Gene ◽  
Clinical Severity ◽  
Globin Genes ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Globin Gene Cluster ◽  
Increased Risk ◽  
Alpha Globin

Abstract Abstract 2011 Poster Board I-1033 Introduction The clinical severity of thalassemia intermedia depends on the degree of a/non-a-chains iimbalance. Among the molecular mechanisms responsible for thalassemia intermedia is the coinheritance of excessive a-globin gene production with a defective beta-globin gene. Materials and Methods: we describe an Italian family where thalassemia intermedia apparently segregates as a dominant form but it tourned out to be due to the coinheritance of a beta-globin mutation and a duplication of the alpha-globin gene cluster. The father (aged 51yrs) showed a well tolerated severe chronic hemolytic anemia (Hb 7.5-8.5 g/dL) not transfusion dependent, jaundice, splenomegaly and leg ulcers:The mother (aged 46yrs) has a completely normal hematological and hemoglobin pattern. Two sons (19 and 14 yrs) showed more severe clinical manifestations than the father. They underwent splenectomy at 12 and 13 years respectively without any benefit and afterwards they become transfusion dependent. Results: The hemoglobin analysis revealed that the father and the sons were heterozygotes for the beta mutation IVSI-110 G>A. MLPA analysis of the alpha-globin gene cluster disclosed a full duplication of the alpha-globin locus, spanning a 175 kb from the telomere to the 3'HVR downstream of the alpha-globin gene and including the upstream regulatory element HS-40. This rearrangement increases the number of the active alpha-globin genes in cis from 2 to 4.Surprisengly it was found in heterozygosis in both parents and in homozygosis in both sons. The hematological and molecular data of the family are reported in the table. In the father the 6 alpha-globin genes led to increased synthesis of alpha-chains; the coinheritance with a beta-thalassemia mutation causes a moderate/severe thalassemia intermedia phenotype. The presence of 8 alpha-globin genes in the sons raises further the degree of globin-chains imbalance and exacerbates the clinical phenotype. It is important to note that splenectomy worsened the clinical course.in the 2 homozygotes for the alpha duplication. Conclusions: Based also on previous experience we suggest that splenectomy in patients with a real excess of alphaa chain production is unconvenient since a large amount of circulating red cells with precipitated alpha chains may be responsible for increased hemolysis as well as increased risk of thrombosis This family moreover raises concerns regarding genetic counselling, suggesting that whenever one of the partner is affected by TI it is advisable a complete molecular screening of the couple in order to exclude any possible alpha gene defects interaction Disclosures: No relevant conflicts of interest to declare.

Long Term Use of Hydroxyurea In Patients with β-Thalassemia In Southern Iran

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2061-2061
Author(s):  
Mehran Karimi ◽  
Sezaneh Haghpanah ◽  
Majid Yavarian ◽  
Ali Farhadi ◽  
Abdolreza Afrasiabi ◽  
...  
Keyword(s):  
Side Effects ◽  
Blood Transfusion ◽  
Adverse Effects ◽  
Globin Gene ◽  
Gene Mutations ◽  
Beta Globin ◽  
Beta Globin Gene ◽  
Clinical Responses ◽  
Group 2 ◽  
Xmni Polymorphism

Abstract Abstract 2061 Introduction: Hydroxyurea(HU) is an antimetabolite agent that also promotes production of fetal hemoglobin (HbF). Reports on the use of HU in patients with thalassemia major (TM) have revealed a reduction in blood transfusion dependency. Due to lesser α/β globin imbalance in thalassemia intermedia (TI) compared with TM, better clinical responses are expected in patients with TI. This study was undertaken to evaluate hematological and clinical responses of patients with β-thalassemia to HU therapy as well as adverse effects of HU and Beta globin gene mutations of patients in a period of thirteen years in southern Iran. Methods: Two hundred patients; mean age of 21±7, ranged from 5 to 40 years enrolled in this study. Patients divided into two groups. Group 1 consisted of 143 transfusion-dependent thalassemia patients after age of two. Group 2 consisted of 57 TI patients without any history of blood transfusion or long interval transfusion. Mean dose of HU was 9.9±2 mg/kg/day, range of 8–15mg/kg/day. Response to HU was defined as increasing Hb level at least 1g/dl after 3 months of starting HU and/or decrease or cessation of the need for blood transfusion. Investigated variables included Hb, MCV, MCH, HbF, and HbA1 in laboratory results as well as spleen size, energy state, facial changes (head circumference), and the need for blood transfusion in clinical findings. The patients were followed by Hb electrophoresis, Complete Blood Count, serum ferritin and chemistry panel in appropriate intervals. The assessment of adverse effects in patients was conducted by pediatric hematologists. Genomic DNA extracted from peripheral leukocyte by Giagen DNA extraction kit. Beta globin gene mutations were determined by ARMS based PCR and confirmed by sequencing. XmnI polymorphism at -153 gG after PCR, was characterized by RFLP method and electrophoresis on 2% agarose. Statistical analysis was done by SPSS v. 15 using student’ t-test, paired t-test, and chi square test. Results: Of the 143 patients in group 1who were transfusion-dependent, 101 patients became transfusion-free and 28of them needed 1–4 transfusions per year. In this group, 14 patients had no response to HU and excluded from the study. All of the patients in group 2 were completely transfusion-free with acceptable Hb level at the end of study. Overall the mean Hb level of the patients after HU therapy was (9.4± 1.3). Exercise tolerance increased in 97% of the patients. No significant facial changes were observed in the patients at the end of study. From 73 non splenectomized patients, 83% had no change in spleen size. Adverse effects of HU were recorded in 44 of 200 patients. The most common side effects were dermatologic adverse effects followed by neurological and gastrointestinal side effects. Hematological malignancy and toxicity or any sign of bone marrow suppression were not observed in the patients during HU therapy. The presence of adverse effects in patients significantly increased by increasing age (p<0.001) and splenectomy (p< 0.05). But it had no significant relationship with sex, HU dose, or duration of treatment (p>0.05). Up to now, the frequency of beta globin gene mutations and XmnI polymorphism in 150 patients has been characterized (Tables 1 and Table 2). The most frequent beta globin gene mutation and XmnI polymorphism in our patients were homo IVS II-1(40.6%) and +/+ (59%) respectively. Conclusion: In our study HU was effective for decreasing or cessation the need of regular blood transfusion as well as increasing Hb level in β-thalassemia patients. Also all of the patients could tolerate low-dose treatment with HU in this period without any major side effects. So HU could be a safe alternative to blood transfusion in transfusion-dependent β-thalassemia patients after age of 2 or help to increase Hb level in untransfused TI patients. Disclosures: No relevant conflicts of interest to declare.

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