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1.  Distribution of β-Globin Gene Mutations in Thalassemia Minor Population of Kerman Province, Iran 
Mutations in β-globin gene may result in β-thalassemia major, which is one of the most common genetic disorders in Iran and some other countries. Knowing the beta-globin mutation spectrum improves the efficiency of prenatal diagnosis in the affected fetuses (major β-thalassemia) of heterozygote couples.
Couples with high hemoglobin A2 and low mean corpuscular volume were studied as suspicious of β-thalassemia carriers in Genetic Laboratory of Afzalipour Hospital, Kerman, Iran. We used amplification refractory mutation system, reverse hybridization, and DNA sequencing to determine the spectrum of β-globin gene mutation in the people who involved with β-thalassemia minor in this province.
Among the 266 subjects, 17 different types of mutation in β-globin gene were identified. Three of the mutations account for 77.1% of the studied cases. IVSI-5(G> C) was the most frequent mutation (66.2%) followed by IVSII-I (G> A) (6%) and Fr 8–9 (+G) (4.9%). The less frequent mutations include: IVSI-6(T> C), codon 15 (G>A), codon 44 (-C), codon 39 (C>T), codon 8 (-AA), codon30 (G> C), IVSI-110 (G > A), codon 36–37 (-T), 619bp deletion, codon 5 (-CT), IVSI-25bp del, codon 41–42(-TTCT), IVSI-I (G> A), and βnt30 (T>A) were accounted for 19.5%. Unknown alleles comprised 3.4% of the mutations.
However, the frequencies of different mutations reported here are significantly different from those found in other part of the world and even other Iranian provinces. Reporting a number of these mutations in the neighboring countries such as Pakistan can be explained by gene flow phenomenon.
PMCID: PMC3481756  PMID: 23113009
β-globin gene; Mutations; β-thalassemia; Iran
2.  β-Globin chain abnormalities with coexisting α-thalassemia mutations 
The frequency of hemoglobinopathies is still high in Adana, the biggest city of the Cukurova Region that is located in the southern part of Turkey. Our aim was to identify the concomitant mutations in α- and β-globin genes which lead to complex hemoglobinopathies and to establish an appropriate plan of action for each subject, particularly when prenatal diagnosis is necessary.
Material and methods
We studied the association between the β-globin gene and α-thalassemia genotypes. The reverse hybridization technique was employed to perform molecular analysis, and the results were confirmed by amplification refractory mutation system (ARMS) or restriction fragment length polymorphism (RFLP) technique.
We evaluated 36 adult subjects (28 female and 8 male; age range: 18-52 years) with concomitant mutations in their α- and β-globin genes. The –α3.7/αα deletion was the commonest defect in the α-chain as expected, followed by α3.7/–α3.7 deletion. Twenty-five of 36 cases were sickle cell trait with coexisting α-thalassemia, while seven Hb S/S patients had concurrent mutations in their α-genes. The coexistence of αPolyA-2α/αα with Hb A/D and with Hb S/D, which is very uncommon, was also detected. There was a subject with compound heterozygosity for β-globin chain (–α3.7/αα with IVSI.110/S), and also a case who had –α3.7/αα deletion with IVSI.110/A.
Although limited, our data suggest that it would be valuable to study coexisting α-globin mutations in subjects with sickle cell disease or β-thalassemia trait during the screening programs for premarital couples, especially in populations with a high frequency of hemoglobinopathies.
PMCID: PMC3460491  PMID: 23056075
a-globin gene; b-globin gene; mutation; S-a-thalassemia; sickle cell anemia
3.  Beta-globin Gene Mutations in Turkish Children with Beta-Thalassemia: Results from a Single Center Study 
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.
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%).
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.
PMCID: PMC3787702  PMID: 24106605
4.  Application of diagnostic methods and molecular diagnosis of hemoglobin disorders in Khuzestan province of Iran 
The hemoglobinopathies refer to a diverse group of inherited disorders characterized by a reduced synthesis of one or more globin chains (thalassemias) or the synthesis of structurally abnormal hemoglobin (Hb). The thalassemias often coexist with a variety of structural Hb variants giving rise to complex genotypes and an extremely wide spectrum of clinical and hematological phenotypes. Hematological and biochemical investigations and family studies provide essential clues to the different interactions and are fundamental to DNA diagnostics of the Hb disorders. Although DNA diagnostics have made a major impact on our understanding and detection of the hemoglobinopathies, DNA mutation testing should never be considered a shortcut or the test of first choice in the workup of a hemoglobinopathy.
A careful three-tier approach involving: (1) Full blood count (2) Special hematological tests, followed by (3) DNA mutation analysis, provides the most effective way in which to detect primary gene mutations as well as gene-gene interactions that can influence the overall phenotype. With the exception of a few rare deletions and rearrangements, the molecular lesions causing hemoglobinopathies are all identifiable by PCR-based techniques. Furthermore, each at-risk ethnic group has its own combination of common Hb variants and thalassemia mutations. In Iran, there are many different forms of α and β thalassemia. Increasingly, different Hb variants are being detected and their effects per se or in combination with the thalassemias, provide additional diagnostic challenges.
We did step-by-step diagnosis workup in 800 patients with hemoglobinopathies who referred to Research center of Thalassemia and Hemoglobinopathies in Shafa Hospital of Ahwaz Joundishapour University of medical sciences, respectively. We detected 173 patients as iron deficiency anemia (IDA) and 627 individuals as thalassemic patients by use of different indices. We have successfully detected 75% (472/627) of the β-thalassemia mutations by using amplification refractory mutation system (ARMS) technique and 19% (130/627) of the β-thalassemia mutations by using Gap-PCR technique and 6% (25/627) as Hb variants by Hb electrophoresis technique. We did prenatal diagnosis (PND) for 176 couples which had background of thalassemia in first pregnancy. Result of PND diagnosis in the first trimester was 35% (62/176) affected fetus with β-thalassemia major and sickle cell disease that led to termination of the pregnancy.
Almost all hemoglobinopathies can be detected with the current PCR-based assays with the exception of a few rare deletions. However, the molecular diagnostic service is still under development to try and meet the demands of the population it serves. In the short term, the current generation of instruments such as the capillary electrophoresis systems, has greatly simplified DNA sequence analysis.
PMCID: PMC3168155  PMID: 21957335
α and β-thalassemia; hemoglobin variants; hemoglobinopathies; iron deficiency anemia; polymerase chain reaction; prenatal diagnosis
5.  Molecular Bases of β-Thalassemia in the Eastern Province of Saudi Arabia 
β-thalassemia is a group of heterogeneous recessive disorders common in many parts of the world. Al-Qatif and Al-Hassa oases in the Eastern Province of Saudi Arabia are regions known for high frequency of these disorders. Using two molecular methods, based on multiplexing-amplification refractory system and reverse hybridization principles, the spectrum of β-thalassemia in the region was studied. Sixty-nine subjects with known β-thalassemia disease and volunteers with high hemoglobin A2(HbA2) and low mean corpuscular volume (MCV) were included in this study. Ten mutations were detected in 91% of the subjects under study. Six of these mutations had previously been observed while the other four mutations are reported here for the first time. In addition, four of the mutations accounted for 76.8% of the subjects studied. IVSII-1 (G > A), IVSI-5 (G > A), and codon 39 (C > T) mutations were found to be the most frequent. However, the frequencies of different mutations reported here are slightly different from those reported earlier. A number of these mutations were also found in the neighboring countries, which can be explained in terms of gene flow.
PMCID: PMC1361487  PMID: 16489266
6.  Prevalence of hemoglobinopathy, ABO and rhesus blood groups in rural areas of West Bengal, India 
Hemoglobinopathies are a group of inherited disorders of hemoglobin synthesis. It could be formed a fatal scenario in concern of lacking of actual information. Beside this, ABO and Rh blood grouping are also important matter in transfusion and forensic medicine and to reduce new born hemolytic disease (NHD).
Materials and Methods:
The spectrum and prevalence of various hemoglobinopathies, ABO and rhesus (Rh) blood groups was screened among patients who visited B.S. Medical College and Hospital, Bankura, West Bengal, India. This study was carried out on 958 patients of different ages ranging from child to adults from January to June 2011. High-performance liquid chromatography (HPLC), complete blood count (CBC) and hemagglutination technique were performed for the assessment of abnormal hemoglobin variants, ABO and Rh blood groups, respectively.
Results from this study had been shown that there was high prevalence of hemoglobinpathies (27.35%) where β-thalassemia in heterozygous state occurred more frequent than other hemoglobinopathies. Out of 958 patients, 72.65% were HbAA and 27.35% were hemoglobinopathies individuals where 17.64% β-thalassemia heterozygous, 2.92% β-thalassemia homozygous, 3.86% HbAE, 1.15% HbAS trait, 1.25% HbE-β thalassemia trait and 0.52% HbS-β thalassemia trait were found. No incidence of HbSS, HbSC, HbCC, HbD and other variants of hemoglobinpathies were observed. The gene frequencies with respect to ABO systems had been shown as O > B > A > AB. Blood group O was the highest (35.8%) and the least percentage distribution was blood group AB (6.68%). Rhesus positive (Rh+) were 97.7%, while the remaining was 2.3% Rhesus negative (Rh-). The frequencies of A+, B+, AB+, and O+ blood groups were 22.44%, 33.61%, 6.58%, and 35.07%, respectively.
Remarkable percentages of hemoglobinopathies were prevalent from the present study. An extensive screening of the population is needed to assess the prevalence of hemoglobinopathies, which will help in identification of carriers of hemoglobinopathies and further it will be of assistance in taking adequate therapeutic and preventive measures.
PMCID: PMC3687885  PMID: 23798945
ABO; blood groups; hemoglobinopathy; HPLC; rhesus; West Bengal
7.  Molecular analysis of beta-globin gene mutations among Thai beta-thalassemia children: results from a single center study 
Beta-thalassemia is one of the most common genetic disorders in Thailand. Clinical phenotype ranges from silent carrier to clinically manifested conditions including severe beta-thalassemia major and mild beta-thalassemia intermedia.
This study aimed to characterize the spectrum of beta-globin gene mutations in pediatric patients who were followed-up in Phramongkutklao Hospital.
Patients and methods
Eighty unrelated beta-thalassemia patients were enrolled in this study including 57 with beta-thalassemia/hemoglobin E, eight with homozygous beta-thalassemia, and 15 with heterozygous beta-thalassemia. Mutation analysis was performed by multiplex amplification refractory mutation system (M-ARMS), direct DNA sequencing of beta-globin gene, and gap polymerase chain reaction for 3.4 kb deletion detection, respectively.
A total of 13 different beta-thalassemia mutations were identified among 88 alleles. The most common mutation was codon 41/42 (-TCTT) (37.5%), followed by codon 17 (A>T) (26.1%), IVS-I-5 (G>C) (8%), IVS-II-654 (C>T) (6.8%), IVS-I-1 (G>T) (4.5%), and codon 71/72 (+A) (2.3%), and all these six common mutations (85.2%) were detected by M-ARMS. Six uncommon mutations (10.2%) were identified by DNA sequencing including 4.5% for codon 35 (C>A) and 1.1% initiation codon mutation (ATG>AGG), codon 15 (G>A), codon 19 (A>G), codon 27/28 (+C), and codon 123/124/125 (-ACCCCACC), respectively. The 3.4 kb deletion was detected at 4.5%. The most common genotype of beta-thalassemia major patients was codon 41/42 (-TCTT)/codon 26 (G>A) or betaE accounting for 40%.
All of the beta-thalassemia alleles have been characterized by a combination of techniques including M-ARMS, DNA sequencing, and gap polymerase chain reaction for 3.4 kb deletion detection. Thirteen mutations account for 100% of the beta-thalassemia genes among the pediatric patients in our study.
PMCID: PMC4266330  PMID: 25525381
mutation analysis; beta-globin gene; Thai children
8.  The Prevalence of Anemia and Hemoglobinopathies in the Hematologic Clinics of the Kermanshah Province, Western Iran 
Hemoglobinopathies are the most common single gene disorders worldwide with a considerable frequency in certain area particularly Mediterranean and Middle Eastern countries. Hemoglobinopathies include structural variants of hemoglobin (Hb S, Hb C, HbE,…) and thalassaemias which are inherited defects in the globin chains synthesis. The present study was conducted to determine the prevalence of hemoglobinopathies in western Iranian patients. A total of 344 patients (151 males and 193 females) with abnormal CBC and/or hemoglobin electrophoresis were enrolled in the present study. Cellulose acetate gel electrophoresis was performed for all patients and abnormal bands were identified by citrate agar gel electrophoresis and PCR based methods. Iron deficiency anemia (IDA) was present in 156 (45.3%) individuals. Thirty four (9.8%) patients had both iron deficiency anemia and α-thalassemia trait trait, 41(11.9%) patients were with both iron deficiency anemia and minor β-thalassemia. There were 31(9%) patients with α-thalassemia trait and 5 (2.2%) patients with Hb H disease. Fifty six (16.2%) patients had minor β-thalassemia. Also, there were 10 (2.9%) individuals homozygous for hemoglobin D-Punjab and one patient with hemoglobin G (0.3%). There was one sample with hemoglobin C. Further, we found 3 patients (0.9%) with sickle cell trait and more 3 patients (0.8%) with S/ β +–thalassemia. Our results indicated that the most frequent cause of hypochromic and/or microcytic anemia in our population was IDA and the minor β-thalassemia was the second cause that needs to more attention in screening programs.
PMCID: PMC4003441  PMID: 24800037
Hemoglobinopathies; α-thalassemia; β-thalassemia; Iron deficiency anemia; Anemia
9.  Increased Microerythrocyte Count in Homozygous α+-Thalassaemia Contributes to Protection against Severe Malarial Anaemia 
PLoS Medicine  2008;5(3):e56.
The heritable haemoglobinopathy α+-thalassaemia is caused by the reduced synthesis of α-globin chains that form part of normal adult haemoglobin (Hb). Individuals homozygous for α+-thalassaemia have microcytosis and an increased erythrocyte count. α+-Thalassaemia homozygosity confers considerable protection against severe malaria, including severe malarial anaemia (SMA) (Hb concentration < 50 g/l), but does not influence parasite count. We tested the hypothesis that the erythrocyte indices associated with α+-thalassaemia homozygosity provide a haematological benefit during acute malaria.
Methods and Findings
Data from children living on the north coast of Papua New Guinea who had participated in a case-control study of the protection afforded by α+-thalassaemia against severe malaria were reanalysed to assess the genotype-specific reduction in erythrocyte count and Hb levels associated with acute malarial disease. We observed a reduction in median erythrocyte count of ∼1.5 × 1012/l in all children with acute falciparum malaria relative to values in community children (p < 0.001). We developed a simple mathematical model of the linear relationship between Hb concentration and erythrocyte count. This model predicted that children homozygous for α+-thalassaemia lose less Hb than children of normal genotype for a reduction in erythrocyte count of >1.1 × 1012/l as a result of the reduced mean cell Hb in homozygous α+-thalassaemia. In addition, children homozygous for α+-thalassaemia require a 10% greater reduction in erythrocyte count than children of normal genotype (p = 0.02) for Hb concentration to fall to 50 g/l, the cutoff for SMA. We estimated that the haematological profile in children homozygous for α+-thalassaemia reduces the risk of SMA during acute malaria compared to children of normal genotype (relative risk 0.52; 95% confidence interval [CI] 0.24–1.12, p = 0.09).
The increased erythrocyte count and microcytosis in children homozygous for α+-thalassaemia may contribute substantially to their protection against SMA. A lower concentration of Hb per erythrocyte and a larger population of erythrocytes may be a biologically advantageous strategy against the significant reduction in erythrocyte count that occurs during acute infection with the malaria parasite Plasmodium falciparum. This haematological profile may reduce the risk of anaemia by other Plasmodium species, as well as other causes of anaemia. Other host polymorphisms that induce an increased erythrocyte count and microcytosis may confer a similar advantage.
Karen Day and colleagues show that increased microcytic erythrocyte count may contribute substantially to the protection of α+-thalassaemia-homozygous children against severe malaria anaemia.
Editors' Summary
Mutations (changes in the DNA that encodes proteins) continually arise within human populations. Harmful mutations that affect an individual's ability to reproduce usually disappear, but most other mutations persist at a low frequency. Some mutations, however, protect their human carriers against specific disease-causing organisms, and consequently occur at high frequencies in human populations that live in places where these organisms are common. For example, the inherited blood disorder α+-thalassemia, which is common in Africa and Southeast Asia, provides protection against malaria, a parasitic disease that occurs in tropical and subtropical parts of the world. α+-Thalassemia is caused by the loss of one or more of the genes that encode the α chains of hemoglobin, the red blood cell (erythrocyte) protein that carries oxygen around the body. These α chains are normally encoded by four genes, two on each Chromosome 16 (all chromosomes come in pairs). People with heterozygous α+-thalassemia lack one copy of the α chain gene and have a –α/αα genotype (genetic makeup). People with homozygous α+-thalassemia lack one copy of the gene on each chromosome (they have a –α/–α genotype) and have mild “microcytic anemia,” a condition characterized by increased numbers of abnormally small erythrocytes (microcytosis) that contain reduced amounts of hemoglobin.
Why Was This Study Done?
Paradoxically, although homozygous α+-thalassemia causes mild anemia, it provides protection against severe malarial anemia, a potentially fatal complication of malaria. Malaria parasites cause anemia because they multiply inside erythrocytes and rupture them. Scientists originally thought that α+-thalassemia protects against malaria by interfering with the parasite's ability to infect erythrocytes, but the evidence collected so far does not support this hypothesis. In this study, therefore, the researchers have investigated whether the microcytosis and increased erythrocyte count associated with α+-thalassemia might be responsible for the protection that this blood disorder provides against severe malarial anemia. Specifically, they asked whether this hematological (blood) profile protects against severe malarial anemia because people with the –α/–α genotype lose less hemoglobin for a given degree of malaria-induced erythrocyte loss than do those with the normal genotype.
What Did the Researchers Do and Find?
A study done in the mid 1990s in children living on the north coast of Papua New Guinea (where 68% of the population has α+-thalassemia) showed that homozygous α+-thalassemia protects against severe malaria. To investigate why, the researchers re-analyzed the genotype-specific reduction in erythrocyte counts and hemoglobin levels associated with acute malarial disease in these children and developed a simple mathematical model to predict hemoglobin levels after malaria infection. They found that when malarial infection reduced the number of erythrocytes per liter of blood by more than 1.1 × 1012 (the average measured loss of erythrocytes in this population because of malaria was 1.5 × 1012 per liter), children with homozygous α+-thalassemia lost less hemoglobin than did those with the normal genotype. Furthermore, children with homozygous α+-thalassemia needed a 10% greater reduction in their red blood cell count than children with the normal genotype for their hemoglobin levels to fall below the value that defines severe malarial anemia.
What Do These Findings Mean?
These findings suggest that the increased number of abnormally small erythrocytes associated with homozygous α+-thalassemia might be responsible for the protection against severe malarial anemia that this blood disorder provides, because more erythrocytes have to be destroyed by the parasite to reduce hemoglobin concentrations to a dangerous level than in people with the normal genotype. In other words, a lower concentration of hemoglobin per erythrocyte coupled with a larger population of erythrocytes might be advantageous in the face of the large reduction in erythrocyte numbers caused by infection with malaria parasites. The researchers note that their study population was infected with only one type of malaria parasite (Plasmodium falciparum), but speculate that the hematological profile associated with α+-thalassemia might also prevent other Plasmodium species causing anemia. Futhermore, they suggest, other mutations that increase the erythrocyte count and cause microcytosis might protect against severe malaria anemia in a similar fashion.
Additional Information.
Please access these Web sites via the online version of this summary at
The MedlinePlus encyclopedia contains pages on thalassemia and on malaria (in English and Spanish)
Detailed information is available on thalassemia (including useful links to other resources) from the US National Heart Lung and Blood Institute, from the US National Human Genome Research Institute, from the Cooley's Anemia Foundation, and from MedlinePlus
The US Centers for Disease Control and Prevention provide information on malaria (in English and Spanish)
Information is also available from the World Health Organization on malaria (in English, Spanish, French, Russian, Arabic, and Chinese)
PMCID: PMC2267813  PMID: 18351796
10.  Birth of Healthy Children After Preimplantation Diagnosis of Thalassemias 
Background:Preimplantation genetic diagnosis (PGD) allows couples at risk of having children with thalassemia to ensure the healthy outcome of their pregnancy.
Methods:Seventeen PGD clinical cycles were initiated for Cypriot couples at risk of having children with different thalassemia mutations, including IVS1-110, IVSI-6, and IVSII-745. Unaffected embryos for transfer were selected by testing oocytes, using first and second polar body (PB) removal and nested polymerase chain reaction analysis followed by restriction digestion.
Results:Unaffected embryos were selected in 16 of 17 PGD cycles. Of 166 oocytes studied from these cycles, 110 were analyzed by sequential analysis of both the first and the second PB, resulting in preselection and transfer of 45 unaffected embryos. This resulted in seven pregnancies and in the birth of five healthy thalassemia-free children. The embryos predicted to have inherited the affected allele were not transferred. Analysis of these embryos confirmed the PB diagnosis.
Conclusions:Sequential first and second PB testing of oocytes is reliable for PGD of thalassemia and is a feasible alternative to prenatal diagnosis in high-risk populations.
PMCID: PMC3455758  PMID: 10224564
preimplantation genetic diagnosis; thalassemia; multiplex nested PCR; allele dropout
11.  Hemoglobin Disorders in South India 
ISRN Hematology  2011;2011:748939.
Cation exchange-high performance liquid chromatography (CE-HPLC) is increasingly being used as a first line of investigation for hemoglobinopathies and thalassemias. Together with a complete blood count, the CE-HPLC is effective in categorizing hemoglobinopathies as traits, homozygous disorders and compound heterozygous disorders. We carried out a one year study in Apollo Hospitals, Chennai (Tamil Nadu, South India) during which 543 abnormal chromatogram patterns were seen. The commonest disorder we encountered was β-thalassemia trait (37.9%), followed by HbE trait (23.2%), homozygous HbE disease (18.9%), HbS trait (5.3%), HbE β-thalassemia (4.6%), HbS β-thalassemia (2.5%), β-thalassemia major (2.3%), HbH (1.6%), homozygous HbS (1.4%), HbD trait (0.7%). The average value of HbA2 in β-thalassemia minor was 5.4%. β-thalassemia major had an average HbF of 88% and in HbH the mean A2 was 1.4%. Among the HbE disorders the HbA2 + HbE was 30.1% in the heterozygous state, 90.8% in the homozygous state and 54.8% in HbE β-thalassemia. In the sickle cell disorders, HbS varied from 30.9% in the trait to 79.9% in the homozygous state to 65.6% in HbS β-thalassemia.
PMCID: PMC3199938  PMID: 22084704
12.  Prenatal Diagnosis of Different Polymorphisms of β-globin Gene in Ahvaz 
Hemoglobinopathy and thalassemia are prevalent genetic disorders throughout the world. Beta thalassemia is one of these disorders with high prevalence in Iran, especially in Khuzestan province. In this study, the rate of different mutations in β-globin gene for prenatal diagnosis in fetal samples was evaluated.
Materials and methods
In this experimental pilot study, 316 fetal samples (chorionic villus or amniotic fluid) suspicious to hemoglobin disorders were enrolled. Afterwards, DNA was extracted and PCR and DNA sequencing were used for evaluation of different mutations in β-globin gene.
Amongst 316 samples evaluated for prenatal diagnosis, 180 cases (56.8%) were carrying at least one mutated gene of β-thalassemia. In addition, results showed that CD 36-37 (- T) and IVS II-1 (G > A) polymorphisms are the most prevalent polymorphisms of β-thalassemia in Ahvaz city with 13.9% and 10.1% rates, respectively.
Using molecular tests for prenatal diagnosis is considered an efficient approach for reducing the birth of children with hemoglobinopathy and identification of prevalent mutations in each region.
PMCID: PMC3913140  PMID: 24505523
Hemoglobinopathy; β-thalassemia; Prenatal diagnosis; Polymorphism
13.  Gene Therapy in Thalassemia and Hemoglobinopathies 
Sickle cell disease (SCD) and ß-thalassemia represent the most common hemoglobinopathies caused, respectively, by the alteration of structural features or deficient production of the ß-chain of the Hb molecule. Other hemoglobinopathies are characterized by different mutations in the α- or ß-globin genes and are associated with anemia and might require periodic or chronic blood transfusions. Therefore, ß-thalassemia, SCD and other hemoglobinopathies are excellent candidates for genetic approaches since they are monogenic disorders and, potentially, could be cured by introducing or correcting a single gene into the hematopoietic compartment or a single stem cell. Initial attempts at gene transfer of these hemoglobinopathies have proved unsuccessful due to limitations of available gene transfer vectors. With the advent of lentiviral vectors many of the initial limitations have been overcame. New approaches have also focused on targeting the specific mutation in the ß-globin genes, correcting the DNA sequence or manipulating the fate of RNA translation and splicing to restore ß-globin chain synthesis. These techniques have the potential to correct the defect into hematopoietic stem cells or be utilized to modify stem cells generated from patients affected by these disorders. This review discusses gene therapy strategies for the hemoglobinopathies, including the use of lentiviral vectors, generation of induced pluripotent stem cells (iPS) cells, gene targeting, splice-switching and stop codon readthrough.
PMCID: PMC3033156  PMID: 21415990
14.  The spectrum of beta thalassaemia mutations in the UAE national population. 
Journal of Medical Genetics  1994;31(1):59-61.
The beta thalassaemia alleles in 50 beta thalassaemia heterozygotes originating from many parts of the United Arab Emirates (UAE) have been characterised using the allele specific priming technique of the polymerase chain reaction (PCR). The IVSI-5 (G-->C) mutation was found to be present in 66%, while six other alleles occurred at the much lower frequencies of 2% to 8%. These were codon 8/9 (+G), IVSI-1, 3' end (-25 bp), codon 5 (-CT), IVSII-1 (G-->A), codon 30 (G-->C), and codon 15 (G-->A). The mutation types and percentages are compared with other Mediterranean Arab countries and neighbouring areas. It is proposed that IVSI-5 and other Asian Indian mutations were introduced into the UAE by population migration from the region previously known as Baluchistan. These findings should be useful for genetic counselling and the development of a first trimester prenatal diagnosis programme based on direct detection of mutations in the UAE.
PMCID: PMC1049601  PMID: 8151640
15.  Genetic Epidemiology, Hematological and Clinical Features of Hemoglobinopathies in Iran 
BioMed Research International  2013;2013:803487.
There is large variation in the molecular genetics and clinical features of hemoglobinopathies in Iran. Studying structural variants of hemoglobin demonstrated that the β-chain variants of hemoglobin S and D-Punjab are more prevalent in the Fars (southwestern Iran) and Kermanshah (western Iran) provinces, respectively. Also, α-chain variants of Hb Q-Iran and Hb Setif are prevalent in western Iran. The molecular basis and clinical severity of thalassemias are extremely heterogenous among Iranians due to the presence of multiethnic groups in the country. β-Thalassemia is more prevalent in northern and southern Iran. Among 52 different β-thalassemia mutations that have been identified among Iranian populations, IVSII-1 G:A is the most frequent mutation in most parts of the country. The presence of IVS I-5 G:C mutation with high frequency in southeastern Iran might reflect gene flow from neighboring countries. A wide spectrum of α-thalassemia alleles has been detected among Iranians with −α3.7 kb as the most prevalent α-thalassemia mutation. The prevention program of thalassemia birth in Iran has reduced the birth rate of homozygous β-thalassemia since the implementation of the program in 1997. In this review genetic epidemiology, clinical and hematological aspects of hemoglobinopathies, and the prevention programs of β-thalassemia in Iran will be discussed.
PMCID: PMC3703361  PMID: 23853772
16.  Molecular epidemiology of β-thalassemia in Pakistan: far reaching implications 
β-thalassaemia, an autosomal recessive hemoglobinopathy, is one of the commonest genetically transmitted disorders throughout the world. Collective measures including carrier identification, genetic counseling and prenatal diagnosis are required for preventing β-thalassemia. To achieve this objective, Identification of the spectrum of genetic mutations, especially for various ethnic backgrounds in Pakistan is necessary. Therefore, we designed a cross sectional prospective study to identify the frequency of various gene mutations in different ethnic groups of Pakistan. Over a 5-year period, DNA from 648 blood samples [including specimens of chorionic villus sampling (CVS)] were analyzed for the twelve most common β-thalassemia mutations found in the Pakistani population by a Multiplex amplification refractory mutation system (ARMS). The most common mutation identified was Intervening Sequence 1-5 (IVS 1-5 (G-C)); accounting for 40.89% mutated alleles, and was represented in all ethnic groups. 15.7 % of the β-thalassemia alleles were found to have Frameshift 8-9 (Fr 8-9) as the second most common mutation Other common genetic defects responsible for β-thalassemia: IVS 1-1 (G-T) was found in 8.17%, Codon-30 (Cd-30 (G-C)) 8.02%, Codon-5(Cd-5 (-CT)) contributed 2.16% and Deletion 619 base pair (Del 619bp) affected 11.11% were found in Pakistan. This large study adds to the pre-existing data in Pakistan. Knowledge of the predominant mutation in a given ethnic group will not only help in developing a short panel of (population-specific) primers of mutations thereby providing a cost-effective method for prenatal diagnosis and also help the clinicians to counsel regarding blood transfusion regimen/ pregnancy termination.
PMCID: PMC3243455  PMID: 22200002
β-thalassemia; genetic mutations; molecular epidemiology; Pakistan
17.  Spectrum of Beta Globin Gene Mutations in Egyptian Children with β-Thalassemia 
The molecular defects resulting in a 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 necessary for carrier screening, genetic counseling, and to offer prenatal diagnosis.
The aim of the work
was to evaluate the different β-globin gene mutations in two hundred β-thalassemic Egyptian children.
Subjects and Methods
This study was carried out on two hundred β-thalassemic Egyptian children covering most Egyptian Governorates including 158 (79%) children with thalassemia major (TM) and 42 (21%) children with thalassemia intermedia(TI). All patients were subjected to meticulous history taking, clinical examination, complete blood count, hemoglobin electrophoresis, serum ferritin and direct fluorescent DNA sequencing of the β-globin gene to detect the frequency of different mutations.
The most common mutations among patients were IVS I-110(G>A) 48%, IVS I-6(T>C) 40%, IVS I-1(G>A) 24%, 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 a considerable variation in phenotypic severity among patients resulting from the interaction of different β∘ and β+mutations. Furthermore, no genotype-phenotype association was found both among the cases with thalassemia major and the cases with thalassemia intermedia.
Direct DNA sequencing provides insights for the frequency of different mutations in patients with β-thalassemia including rare and/or unknown ones. The most common mutations in Egyptian children with beta thalassemia were IVS I-110(G>A) 48%, IVS I-6(T>C) 40%, IVS I-1(G>A)24%, IVS I-5(G>C)10%, IVS II-848 (C>A) 9%, IVS II-745(C>G) 8%, IVS II-1(G>A) 7%.
PMCID: PMC4235483  PMID: 25408857
18.  Antenatal Screening for Identification of Couples for Prenatal Diagnosis of Severe Hemoglobinopathies in Surat, South Gujarat 
Our aim was to identify couples at risk of having a homozygous or compound heterozygous child with a severe hemoglobinopathy by antenatal screening and prenatal diagnosis in Surat, South Gujarat.
Pregnant women were screened for hemoglobinopathies by means of red cell indices, the solubility test, cellulose acetate electrophoresis tests, and confirmation by HPLC. Husbands of the pregnant women having hemoglobinopathies were counseled and screened for hemoglobinopathies. The couples at risk were again counseled and referred to the National Institute of Immunohematology, where mutations in parents and fetuses were identified by molecular analysis. After prenatal diagnosis, the continuing pregnancies were followed up and infants were tested at birth.
Out of 3,009 women, 37.04, 52.6, and 10.3 % were in the first, second, and third trimester of pregnancy, respectively. Among those having hemoglobinopathies, 102 (3.38 %) had the β-thalassemia trait, 46 (1.5 %) the Sickle cell trait, and 26 (0.86) had hemoglobin variants like Hb DPunjab, Hb E, Hb DIran, Hb QIndia, Hb JParis-I, and Hb OIndonesia. Out of the 14 couples at risk of having an affected child, 11 (78.5 %) couples opted for prenatal diagnosis. Three fetuses had homozygous β-thalassemia and hence the pregnancies were terminated. Follow up of normal or heterozygous fetuses confirmed the diagnosis.
During antenatal screening, we found many Hb variants of β and α globin chains. Late antenatal registration, non-cooperation of the husband for investigation, and refusal for prenatal diagnosis are the main hurdles in the hemoglobinopathy prevention program and awareness is necessary.
PMCID: PMC3664685  PMID: 24431619
β-Thalassemia trait; Sickle cell trait; Hb variants; Antenatal screening; Prenatal diagnosis
19.  Efficient Detection of Mediterranean β-Thalassemia Mutations by Multiplex Single-Nucleotide Primer Extension 
PLoS ONE  2012;7(10):e48167.
β-Thalassemias and abnormal hemoglobin variants are among the most common hereditary abnormalities in humans. Molecular characterization of the causative genetic variants is an essential part of the diagnostic process. In geographic areas with high hemoglobinopathy prevalence, such as the Mediterranean region, a limited number of genetic variants are responsible for the majority of hemoglobinopathy cases. Developing reliable, rapid and cost-effective mutation-specific molecular diagnostic assays targeting particular populations greatly facilitates routine hemoglobinopathy investigations. We developed a one-tube single-nucleotide primer extension assay for the detection of eight common Mediterranean β-thalassemia mutations: Codon 5 (-CT); CCT(Pro)->C–, Codon 6 (-A); GAG(Glu)->G-G, Codon 8 (-AA); AAG(Lys)->–G, IVS-I-1 (G->A), IVS-I-6 (T->C), IVS-I-110 (G->A), Codon 39 (C->T), and IVS-II-745 (C->G), as well as the hemoglobin S variant beta 6(A3) Glu>Val. We validated the new assay using previously genotyped samples obtaining 100% agreement between independent genotyping methods. Our approach, applicable in a range of Mediterranean countries, offers a combination of high accuracy and rapidity exploiting standard techniques and widely available equipment. It can be further adapted to particular populations by including/excluding assayed mutations. We facilitate future modifications by providing detailed information on assay design.
PMCID: PMC3482202  PMID: 23110203
20.  The Search for Genetic Modifiers of Disease Severity in the β-Hemoglobinopathies 
Sickle cell disease (SCD) and β-thalassemia, two monogenic diseases caused by mutations in the β-globin gene, affect millions of individuals worldwide. These hemoglobin disorders are characterized by extreme clinical heterogeneity, complicating patient management and treatment. A better understanding of this patient-to-patient clinical variability would dramatically improve care and might also guide the development of novel therapies. Studies of the natural history of these β-hemoglobinopathies have identified fetal hemoglobin levels and concomitant α-thalassemia as important modifiers of disease severity. Several small-scale studies have attempted to identify additional genetic modifiers of SCD and β-thalassemia, without much success. Fortunately, improved knowledge of the human genome and the development of new genomic tools, such as genome-wide genotyping arrays and next-generation DNA sequencers, offer new opportunities to use genetics to better understand the causes of the many complications observed in β-hemoglobinopathy patients. Here I discuss the most important factors to consider when planning an experiment to find associations between β-hemoglobinopathy-related complications and DNA sequence variants, with a focus on how to successfully perform a genome-wide association study. I also review the literature and explain why most published findings in the field of SCD modifier genetics are likely to be false-positive reports, with the goal to draw lessons allowing investigators to design better genetic experiments.
Sickle cell disease and β-thalassemia show extreme clinical heterogeneity. Successfully identifying genetic modifiers of disease severity requires careful experimental design.
PMCID: PMC3475403  PMID: 23028136
21.  Prevalence of β-thalassemia and other haemoglobinopathies in six cities in India: a multicentre study 
Journal of Community Genetics  2012;4(1):33-42.
The population of India is extremely diverse comprising of more than 3,000 ethnic groups who still follow endogamy. Haemoglobinopathies are the commonest hereditary disorders in India and pose a major health problem. The data on the prevalence of β-thalassemias and other haemoglobinopathies in different caste/ethnic groups of India is scarce. Therefore the present multicentre study was undertaken in six cities of six states of India (Maharashtra, Gujarat, West Bengal, Assam, Karnataka and Punjab) to determine the prevalence of haemoglobinopathies in different caste/ethnic groups using uniform methodology. Fifty-six thousand seven hundred eighty individuals (college students and pregnant women) from different caste/ethnic groups were screened. RBC indices were measured on an automated haematology counter while the percentage of HbA2, HbF and other abnormal Hb variants were estimated by HPLC on the Variant Hemoglobin Testing System. The overall prevalence of β-thalassemia trait was 2.78 % and varied from 1.48 to 3.64 % in different states, while the prevalence of β-thalassemia trait in 59 ethnic groups varied from 0 to 9.3 %. HbE trait was mainly seen in Dibrugarh in Assam (23.9 %) and Kolkata in West Bengal (3.92 %). In six ethnic groups from Assam, the prevalence of HbE trait varied from 41.1 to 66.7 %. Few subjects with δβ-thalassemia, HPFH, HbS trait, HbD trait, HbE homozygous and HbE β-thalassemia as well as HbS homozygous and HbS-β-thalassemia (<1 %) were also identified. This is the first large multicentre study covering cities from different regions of the country for screening for β-thalassemia carriers and other haemoglobinopathies where uniform protocols and methodology was followed and quality control ensured by the co-ordinating centre. This study also shows that establishment of centres for screening for β-thalassemia and other haemoglobinopathies is possible in medical colleges. Creating awareness, screening and counselling can be done at these centres. This experience will help to formulate a national thalassemia control programme in India.
PMCID: PMC3537975  PMID: 23086467
β-Thalassemia; Other haemoglobinopathies; Caste/ethnic goups; India; Multicentre study
22.  Genotype-phenotype correlation of β-thalassemia spectrum of mutations in an Indian population 
Hematology Reports  2012;4(2):e9.
Coexistence of thalassemia, hemoglobinopathies and malaria has interested geneticists over many decades. The present study represents such a population from the eastern Indian state of Orissa. Children and their siblings (n=38) were genotyped for β-thalassemia mutations and genotype-phenotype correlation was determined. The major genotype was IVS 1.5 mutation: 26% homozygous (n=10) and 37% (n=14) double heterozygous with other mutations or hemoglobinopathies. Sickle hemoglobin was the major associated hemoglobinopathy (n=12, 32%). Other mutations found were Cd 8/9, HbE and Cd 41/42. The study population did not contain any IVS 1.1 mutations which is the second major Indo-Asian genotype. Genotype-phenotype correlation revealed that genotypes of IVS 1.5, Cd 8/9 Cd 41/42 alone or in association, exhibit severe, moderate and mild severity of thalassemia, respectively. Identification of the mutation at an early age as a part of new born screening and early intervention may help reduce the thalassemia-related morbidity.
PMCID: PMC3401138  PMID: 22826799
β-thalassemia mutations; genotype-phenotype correlation; HbS; IVS 1.5 associated genotypes; malaria.
23.  Clinical, hematologic and molecular variability of sickle cell-β thalassemia in western India 
Indian Journal of Human Genetics  2010;16(3):154-158.
Sickle cell-β thalassemia (HbS-β thalassemia) is a sickling disorder of varying severity, which results from compound heterozygosity for sickle cell trait and β thalassemia trait. The present study was undertaken to determine the genetic factors responsible for the clinical variability of HbS-β thalassemia patients from western India.
Twenty-one HbS-β thalassemia cases with variable clinical manifestations were investigated. The α and β globin gene clusters were studied by molecular analysis.
Thirteen patients showed milder clinical presentation as against eight patients who had severe clinical manifestations. Four β thalassemia mutations were identified: IVS 1-5 (G→C), codon 15 (G→A), codon 30 (G→C) and codon 8/9 (+G). α thalassemia and XmnI polymorphism in homozygous condition (+/+) were found to be common among the milder cases. The βS chromosomes were linked to the typical Arab-Indian haplotype (#31). Framework (FW) linkage studies showed that four β thalassemia mutations were associated with different β globin gene frameworks. Linkage of codon 15 (G→A) mutation to FW2 is being observed for the first time.
The phenotypic expression of HbS-β thalassemia is not uniformly mild and α thalassemia and XmnI polymorphism in homozygous condition (+/+) are additional genetic factors modulating the severity of the disease in the Indian subcontinent.
PMCID: PMC3009427  PMID: 21206704
HbS- β thalassemia; clinical; mutations; framework; India
24.  In Silico Analysis of Single Nucleotide Polymorphism (SNPs) in Human β-Globin Gene 
PLoS ONE  2011;6(10):e25876.
Single amino acid substitutions in the globin chain are the most common forms of genetic variations that produce hemoglobinopathies- the most widespread inherited disorders worldwide. Several hemoglobinopathies result from homozygosity or compound heterozygosity to beta-globin (HBB) gene mutations, such as that producing sickle cell hemoglobin (HbS), HbC, HbD and HbE. Several of these mutations are deleterious and result in moderate to severe hemolytic anemia, with associated complications, requiring lifelong care and management. Even though many hemoglobinopathies result from single amino acid changes producing similar structural abnormalities, there are functional differences in the generated variants. Using in silico methods, we examined the genetic variations that can alter the expression and function of the HBB gene. Using a sequence homology-based Sorting Intolerant from Tolerant (SIFT) server we have searched for the SNPs, which showed that 200 (80%) non-synonymous polymorphism were found to be deleterious. The structure-based method via PolyPhen server indicated that 135 (40%) non-synonymous polymorphism may modify protein function and structure. The Pupa Suite software showed that the SNPs will have a phenotypic consequence on the structure and function of the altered protein. Structure analysis was performed on the key mutations that occur in the native protein coded by the HBB gene that causes hemoglobinopathies such as: HbC (E→K), HbD (E→Q), HbE (E→K) and HbS (E→V). Atomic Non-Local Environment Assessment (ANOLEA), Yet Another Scientific Artificial Reality Application (YASARA), CHARMM-GUI webserver for macromolecular dynamics and mechanics, and Normal Mode Analysis, Deformation and Refinement (NOMAD-Ref) of Gromacs server were used to perform molecular dynamics simulations and energy minimization calculations on β-Chain residue of the HBB gene before and after mutation. Furthermore, in the native and altered protein models, amino acid residues were determined and secondary structures were observed for solvent accessibility to confirm the protein stability. The functional study in this investigation may be a good model for additional future studies.
PMCID: PMC3197589  PMID: 22028795
25.  Prenatal diagnosis of hemoglobinopathies: evaluation of techniques for analysing globin-chain synthesis in blood samples obtained by fetoscopy. 
Three techniques for analysing hemoglobin synthesis in blood samples obtained by fetoscopy were evaluated. Of the fetuses studied, 12 were not at risk of genetic disorders, 10 were at risk of beta-thalassemia, 2 were at risk of sickle cell anemia and 1 was at risk of both diseases. The conventional method of prenatal diagnosis of hemoglobinopathies, involving the separation of globin chains labelled with a radioactive isotope on carboxymethyl cellulose (CMC) columns, was compared with a method involving globin-chain separation by high-pressure liquid chromatography (HPLC) and with direct analysis of labelled hemoglobin tetramers obtained from cell lysates by chromatography on ion-exchange columns. The last method is technically the simplest and can be used for diagnosing beta-thalassemia and sickle cell anemia. However, it gives spuriously high levels of adult hemoglobin in samples containing nonlabelled adult hemoglobin. HPLC is the fastest method for prenatal diagnosis of beta-thalassemia and may prove as reliable as the CMC method. Of the 13 fetuses at risk for hemoglobinopathies, 1 was predicted to be affected, and the diagnosis was confirmed in the abortus. Of 12 predicted to be unaffected, 1 was aborted spontaneously and was unavailable for confirmatory studies, as were 3 of the infants; however, the diagnosis was confirmed in seven cases and is awaiting confirmation when the infant in 6 months old in one case. Couples at risk of bearing a child with a hemoglobinopathy should be referred for genetic counselling before pregnancy or, at the latest, by the 12th week of gestation so that prenatal diagnosis can be attempted by amniocentesis, safer procedure, with restriction endonuclease analysis of the amniotic fluid cells.
PMCID: PMC1862227  PMID: 7139502

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