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  1. Alpha-thalassaemia in association with beta-thalassaemia patients in Malaysia: a study on the co-inheritance of both disorders
    Wee YC, Tan KL, Kuldip K, Tai KS, George E, Tan PC, et al.
    Community Genet, 2008;11(3):129-34.
    PMID: 18376108 DOI: 10.1159/000113874
    BACKGROUND/AIMS: Individuals with double heterozygosity for alpha- and beta-thalassaemia and heterozygous beta-thalassaemia show a similar haematological picture. Co-inheritance of alpha- and beta-thalassaemia in both partners may result in pregnancies with either Hb Bart's hydrops foetalis or beta-thalassaemia major, or pregnancies with both disorders.
    METHODS: The co-inheritance of alpha-thalassaemia in 322 beta-thalassaemia carriers in Malaysia was studied.
    RESULTS: The frequency of alpha-thalassaemia in the beta-thalassaemia carriers was 12.7% (41/322), with a carrier frequency of 7.8% for the SEA deletion, 3.7% for the -alpha(3.7) deletion, 0.9% for Hb Constant Spring and 0.3% for the -alpha(4.2) deletion.
    CONCLUSION: Double heterozygosity for alpha- and beta-thalassaemia was confirmed in 5 out of the 41 couples and the risk of the fatal condition Hb Bart's hydrops foetalis was confirmed in two of these couples. Detection of the Southeast Asian (SEA) deletion in the Malaysian Malays in this study confirms that Hb Bart's hydrops foetalis can occur in this ethnic group. Results of this study have provided new information on the frequency and different types of alpha-thalassaemia (--(SEA), -alpha(3.7) and -alpha(4.2) deletions, Hb Constant Spring) in Malaysian beta-thalassaemia carriers.
    Matched MeSH terms: beta-Thalassemia/diagnosis
  2. Microcytic to hypochromic ratio as a discriminant index of thalassaemia trait in subjects with hypochromic anaemia
    Wee SY, Muhamed Said SS, Raja Sabudin RZA, Alauddin H, Ithnin A
    Malays J Pathol, 2020 Aug;42(2):195-201.
    PMID: 32860371
    INTRODUCTION: Differentiating between thalassaemia and iron deficiency anaemia (IDA) in hypochromic anaemia is a challenge to pathologists as it influences the choice of subsequent specialized confirmatory tests. In this study, we aimed to evaluate the performance of microcytic to hypochromic ratio (MicroR/ Hypo-He, M/H ratio) as a discriminant index in hypochromic anaemia.

    MATERIALS AND METHODS: A retrospective study was carried out on 318 subjects with hypochromic anaemia, which comprised 162 IDA and 156 thalassaemia trait subjects with α-thalassemia, β-thalassemia and HbE trait. Optimal cut-off value, sensitivity and specificity of M/H ratio for thalassaemia trait discrimination was determined using Receiver Operating Characteristic (ROC) analysis.

    RESULTS: Subjects with thalassaemia trait showed higher MicroR compared to IDA ( p< 0.001) while subjects with IDA demonstrated higher Hypo-He than thalassaemia trait (p < 0.001). M/H ratio was significantly higher in thalassaemia trait compared to IDA, with medians of 3.77 (interquartile range: 2.57 - 6.52) and 1.73 (interquartile range: 1.27 - 2.38), respectively (p < 0.001). M/H ratio ≥ 2.25 was the optimal cut-off value for discriminating thalassaemia trait from IDA in hypochromic anaemia, with the area under ROC curve (AUC) of 0.83, sensitivity of 80.8% and specificity of 71.6%.

    CONCLUSIONS: M/H ratio is a useful discriminant index to distinguish thalassaemia trait from IDA in hypochromic anaemia prior to diagnostic analysis for thalassaemia confirmation. High M/H ratio is suggestive of thalassaemia trait than of IDA. However, more studies are required to establish the role of M/H ratio as a screening tool for thalassaemia discrimination in hypochromic anaemia.

    Matched MeSH terms: beta-Thalassemia/diagnosis
  3. Fulltext Characterisation of beta-globin gene mutations in Malaysian children: a strategy for the control of beta-thalassaemia in a developing country
    Thong MK, Tan JA, Tan KL, Yap SF
    J Trop Pediatr, 2005 Dec;51(6):328-33.
    PMID: 15967770 DOI: 10.1093/tropej/fmi052
    beta-thalassaemia major, an autosomal recessive hemoglobinopathy, is one of the most common single gene disorders in multi-racial Malaysia. The control of beta-thalassaemia major requires a multi-disciplinary approach that includes population screening, genetic counselling, prenatal diagnosis and the option of termination of affected pregnancies. To achieve this objective, the molecular characterisation of the spectrum of beta-globin gene mutations in each of the affected ethnic groups is required. We studied 88 consecutive unrelated individuals and their respective families with beta-thalassaemia (74 beta-thalassaemia major, 12 HbE-beta-thalassaemia, 2 with HbE homozygotes) and four individuals with beta-thalassaemia trait that contributed a total 180 alleles for study. Using a 2-step molecular diagnostic strategy consisting of amplification refractory mutation system (ARMS) to identify the 8 most common mutations followed by other DNA-based diagnostic techniques, a total of 177 (98.3 per cent) of the 180 beta-thalassaemia alleles were characterised. One out of 91 (1 per cent) of the Chinese alleles, one out of 46 (2.2 per cent) Malay alleles and one out of two Indian alleles remained unknown. A 100 per cent success rate was achieved in studying the Kadazandusun community in this study. A strategy to identify beta-globin gene mutations in Malaysians with beta-thalassaemia is proposed based on this outcome.
    Matched MeSH terms: beta-Thalassemia/diagnosis
  4. Molecular heterogeneity of beta-thalassaemia in Malaysia: a practical approach to diagnosis
    Thong MK, Law HY, Ng IS
    Ann Acad Med Singap, 1996 Jan;25(1):79-83.
    PMID: 8779552
    The beta-thalassaemia mutations in 20 Malaysian children with beta-thalassaemia major were characterised by using a multi-modal approach, consisting of a slot-blot hybridisation with selected allele-specific oligonucleotides (ASO), followed by reverse dot-blot assay (RDB), amplification refractory mutation system (ARMS) and genomic sequencing. This strategy yielded a 94.4% mutation detection rate. The 6 most common mutations were codons 41/42 (-TTCT), IVS II nt 654(C --> T), IVS I nt 5(G --> C), IVS I nt 1(G -->T), codon 35 (-C) and codon 19 (A --> G), which accounted for 83.3% of all mutations detected. A strategy of initial screening with the above 6 selected ASOs for slot-blot hybridisation followed by RDB assay for the less common Asian mutations would give a mutation identification of 91.7%. Another feasible approach would be to analyse alleles from a particular racial group, by a judicious selection of 4 ASOs common to that particular subpopulation and then supplement this with RDB assay. This could yield a 100% coverage for the Chinese subpopulation in Malaysia. With these strategies, a practical approach has been identified to overcome the pitfalls posed by the molecular heterogeneity of beta-thalassaemia to enable prenatal diagnosis and carrier screening to be carried out. Regional collaborative studies are to be encouraged as an indispensable tool in providing better health care services to our patients.
    Matched MeSH terms: beta-Thalassemia/diagnosis
  5. The use of Taqman genotyping assays for rapid confirmation of β-thalassaemia mutations in the Malays: accurate diagnosis with low DNA concentrations
    Teh LK, Lee TY, Tan JA, Lai MI, George E
    Int J Lab Hematol, 2015 Feb;37(1):79-89.
    PMID: 24725998 DOI: 10.1111/ijlh.12240
    In Malaysia, β-thalassaemia is a common inherited blood disorder in haemoglobin synthesis with a carrier rate of 4.5%. Currently, PCR-incorporating techniques such as amplification refractory mutation system (ARMS) or reverse dot blot hybridization (RDBH) are used in β-thalassaemia mutation detection. ARMS allows single-mutation identification using two reactions, one for wild type and another for mutant alleles. RDBH requires probe immobilization and optimization of hybridization and washing temperatures which is time consuming. The aim of our study was to investigate whether β-thalassaemia mutations can be identified in samples with low DNA concentrations.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  6. Combine-ARMS: a rapid and cost-effective protocol for molecular characterization of beta-thalassemia in Malaysia
    Tan KL, Tan JA, Wong YC, Wee YC, Thong MK, Yap SF
    Genet. Test., 2001;5(1):17-22.
    PMID: 11336396 DOI: 10.1089/109065701750168626
    Beta-thalassemia major patients have chronic anemia and are dependent on blood transfusions to sustain life. Molecular characterization and prenatal diagnosis of beta3-thalassemia is essential in Malaysia because about 4.5% of the population are heterozygous carriers for beta-thalassemia. The high percentage of compound heterozygosity (47.62%) found in beta-thalassemia major patients in the Thalassaemia Registry, University of Malaya Medical Centre (UMMC), Malaysia, also supports a need for rapid, economical, and sensitive protocols for the detection of beta-thalassemia mutations. Molecular characterization of beta-thalassemia mutations in Malaysia is currently carried out using ARMS, which detects a single beta-thalassemia mutation per PCR reaction. We developed and evaluated Combine amplification refractory mutation system (C-ARMS) techniques for efficient molecular detection of two to three beta-thalassemia mutations in a single PCR reaction. Three C-ARMS protocols were evaluated and established for molecular characterization of common beta-thalassemia mutations in the Malay and Chinese ethnic groups in Malaysia. Two C-ARMS protocols (cd 41-42/IVSII #654 and -29/cd 71-72) detected the beta-thalassemia mutations in 74.98% of the Chinese patients studied. The CARMS for cd 41-42/IVSII #654 detected beta-thalassemia mutations in 72% of the Chinese families. C-ARMS for cd 41-42/IVSI #5/cd 17 allowed detection of beta-thalassemia mutations in 36.53% of beta-thalassemia in the Malay patients. C-ARMS for cd 41-42/IVSI #5/cd 17 detected beta-thalassemia in 45.54% of the Chinese patients. We conclude that C-ARMS with the ability to detect two to three mutations in a single reaction provides more rapid and cost-effective protocols for beta-thalassemia prenatal diagnosis and molecular analysis programs in Malaysia.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  7. BamH1 polymorphism in the Chinese, Malays, and Indians in Singapore and its application in the prenatal diagnosis of beta-thalassemia
    Tan JA, Tay SH, Kham KY, Wong HB
    Jpn. J. Hum. Genet., 1993 Sep;38(3):315-8.
    PMID: 7903173 DOI: 10.1007/BF01874141
    The distribution of restriction fragment length polymorphism (RFLP) at the BamH1 site of the beta-globin gene was investigated in the Chinese, Indian, and Malay race in Singapore. The sample comprised of 183 normal individuals and 35 beta-thalassemia carriers in which 13 were couples with at least one beta-major child. The results from this study indicate that BamH1 polymorphism will be informative in 22% of pregnancies at risk for beta-thalassemia major in Chinese, 19% in Malays and 7% in Indians. In prenatal diagnosis using BamH1 polymorphism for one beta-major affected family, the fetus was diagnosed to be normal or beta-carrier. The validity of BamH1 polymorphism in the exclusion of beta-thalassemia major was subsequently confirmed at birth by globin chain biosynthesis.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  8. Thalassemia intermedia in HbH-CS disease with compound heterozygosity for beta-thalassemia: challenges in hemoglobin analysis and clinical diagnosis
    Tan JA, Kok JL, Tan KL, Wee YC, George E
    Genes Genet Syst, 2009 Feb;84(1):67-71.
    PMID: 19420802
    Co-inheritance of alpha-thalassemia with homozygosity or compound heterozygosity for beta-thalassemia may ameliorate beta-thalassemia major. A wide range of clinical phenotypes is produced depending on the number of alpha-thalassemia alleles (-alpha/alphaalpha --/alphaalpha, --/-alpha). The co-inheritance of beta-thalassemia with alpha-thalassemia with a single gene deletion (-alpha/alphaalpha) is usually associated with thalassemia major. In contrast, the co-inheritance of beta-thalassemia with two alpha-genes deleted in cis or trans (--/alphaalpha or -alpha/-alpha) generally produces beta-thalassemia intermedia. In Southeast Asia, the most common defect responsible for alpha-thalassemia is the Southeast Asian (SEA) deletion of 20.5 kilobases. The presence of the SEA deletion with Hb Constant Spring (HbCS) produces HbH-CS disease. Co-inheritance of HbH-CS with compound heterozygosity for beta-thalassemia is very rare. This study presents a Malay patient with HbH-CS disorder and beta degrees/beta+-thalassemia. The SEA deletion was confirmed in the patient using a duplex-PCR. A Combine-Amplification Refractory Mutation System (C-ARMS) technique to simultaneously detect HbCS and Hb Quong Sze confirmed HbCS in the patient. Compound heterozygosity for CD41/42 and Poly A was confirmed using the ARMS. This is a unique case as the SEA alpha-gene deletion in cis (--SEA/alphaalpha) is generally not present in the Malays, who more commonly possess the two alpha-gene deletion in trans (-alpha/-alpha). In addition, the beta-globin gene mutation at CD41/42 is a common mutation in the Chinese and not in the Malays. The presence of both the SEA deletion and CD41/42 in the mother of the patient suggests the possible introduction of these two defects into the family by marriage with a Chinese.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  9. Molecular defects in the beta-globin gene identified in different ethnic groups/populations during prenatal diagnosis for beta-thalassemia: a Malaysian experience
    Tan JA, George E, Tan KL, Chow T, Tan PC, Hassan J, et al.
    Clin Exp Med, 2004 Dec;4(3):142-7.
    PMID: 15599663 DOI: 10.1007/s10238-004-0048-x
    Beta-thalassemia is the most-common genetic disorder of hemoglobin synthesis in Malaysia, and about 4.5% of the population are heterozygous carriers of the disorder. Prenatal diagnosis was performed for 96 couples using the Amplification Refractory Mutation System and Gap-Polymerase Chain Reaction. We identified 17 beta-globin defects-initiation codon for translation (T-G), -29 (A-G), -28 (A-G), CAP +1 (A-C), CD 8/9 (+G), CD 15 (G-A), CD 17 (A-T), CD 19 (A-G), Hb E (G-A), IVS1-1 (G-T), IVS1-5 (G-C), CD 41/42 (-CTTT), CD 71-72 (+A), IVS2-654 (CT), poly A(A-G), 100-kb Ggamma(Agammadeltabeta) degrees and 45-kb Filipino deletions. The 192 beta-alleles studied comprised Chinese (151 patients), Malay (21), Orang Asli from East Malaysia (15), Filipino (1), Indian (1), Indonesian Chinese (2), and Thai (1). In the Chinese, 2 beta-globin defects at CD 41/42 and IVS2-654 were responsible for 74% of beta-thalassemia. beta-mutations at CD 19, IVS1-1 (G-T), IVS1-5, poly A, and hemoglobin E caused 76% of the hemoglobin disorders in the Malays. The Filipino 45-kb deletion caused 73.3% of bthalassemia in the Orang Asli. Using genomic sequencing, the rare Chinese beta-mutation at CD 43 (G-T) was confirmed in 2 Chinese, and the Mediterranean mutation IVS1-1 (G-A) was observed in a Malay beta-thalassemia carrier. The beta-globin mutations confirmed in this prenatal diagnosis study were heterogenous and 65 (68%) couples showed a different globin defect from each other. The use of specific molecular protocols has allowed rapid and successful prenatal diagnosis of beta-thalassemia in Malaysia.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  10. Counseling for prenatal diagnosis and termination of pregnancy due to thalassemia major: a survey of health care workers' practices in Malaysia
    Ngim CF, Lai NM, Ibrahim H
    Prenat Diagn, 2013 Dec;33(13):1226-32.
    PMID: 24014379 DOI: 10.1002/pd.4233
    OBJECTIVE: Genetic counseling for thalassemia carriers is conducted by nongeneticist health care workers (HCWs) in many countries. The aim of the study was to assess Malaysian HCWs' genetic counseling practices with regards to discussing prenatal diagnosis (PND) and termination of pregnancy (TOP) when counseling thalassemia carriers.
    METHOD: A total of 118 Malaysian HCWs (52 doctors and 66 nurses) completed a structured questionnaire that enquired if they would discuss PND and TOP when counseling couples with thalassemia traits, and reasons for their responses were explored.
    RESULTS: All the nurses and 50 (96.1%) doctors were in favor of discussing PND. Only 29 (58%) doctors and 33 (50%) nurses were agreeable to discuss about the option of TOP. Main reasons given for declining to discuss TOP were views that "the condition was not serious enough" (54.9%), TOP is not permissible by their religion (17.6%) and abortion for this indication was illegal (13.7%).
    CONCLUSION: The results showed that HCWs in Malaysia lacked the comprehensive information and necessary skills required when counseling thalassemia carriers. When nongeneticist HCWs are tasked with such responsibilities, their practices and attitudes should be regularly evaluated so that areas of deficiencies could be identified and addressed.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  11. Preimplantation genetic diagnosis for beta-thalassemia using single-cell DNA analysis for codons 17 and 26 of beta-globin gene
    Nasri NW, Jamal AR, Abdullah NC, Razi ZR, Mokhtar NM
    Arch Med Res, 2009 Jan;40(1):1-9.
    PMID: 19064120 DOI: 10.1016/j.arcmed.2008.10.008
    Preimplantation genetic diagnosis (PGD) of monogenic autosomal hereditary disorders following assisted conception usually involves the removal of one or two blastomeres from preimplantation embryos. However, the amount of DNA from a single blastomere is insufficient to amplify the region of interest. Hence, the whole genome amplification (WGA) method is performed prior to amplifying the genes of interest before analysis of DNA material through polymerase chain reaction (PCR).
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  12. A Rare Case of von Willebrand Disease Presenting as Hemolacria and Literature Review
    Nandakumal G, Ismail F, Mohamad NF, Lott PW, Chew KS, Ab Rahman S, et al.
    J Pediatr Hematol Oncol, 2021 04 01;43(3):101-103.
    PMID: 33560075 DOI: 10.1097/MPH.0000000000002077
    Hemolacria is a rare condition that causes a person to produce tears that are partially composed of blood. It can be a presenting feature of certain ocular and systemic conditions. Here, the authors describe an interesting case of a 12-year-old boy with an underlying beta-thalassemia trait, who presented with a 2-day history of bilateral blood-stained tears, and an episode of epistaxis. Ocular examination was normal, and syringing showed no nasolacrimal duct blockage. Systemic examination was unremarkable. Laboratory investigations confirmed type 2 von Willebrand disease. Management of hemolacria remains a clinical challenge given the rare occurrence of the disease. In this case report, the authors discuss the differential diagnosis and management approach to hemolacria.
    Matched MeSH terms: beta-Thalassemia/diagnosis
  13. Fulltext Predictive SNPs for β0-thalassemia/HbE disease severity
    Munkongdee T, Tongsima S, Ngamphiw C, Wangkumhang P, Peerapittayamongkol C, Hashim HB, et al.
    Sci Rep, 2021 05 14;11(1):10352.
    PMID: 33990643 DOI: 10.1038/s41598-021-89641-2
    β-Thalassemia/HbE disease has a wide spectrum of clinical phenotypes ranging from asymptomatic to dependent on regular blood transfusions. Ability to predict disease severity is helpful for clinical management and treatment decision making. A thalassemia severity score has been developed from Mediterranean β-thalassemia patients. However, different ethnic groups may have different allele frequency and linkage disequilibrium structures. Here, Thai β0-thalassemia/HbE disease genome-wild association studies (GWAS) data of 487 patients were analyzed by SNP interaction prioritization algorithm, interacting Loci (iLoci), to find predictive SNPs for disease severity. Three SNPs from two SNP interaction pairs associated with disease severity were identifies. The three-SNP disease severity risk score composed of rs766432 in BCL11A, rs9399137 in HBS1L-MYB and rs72872548 in HBE1 showed more than 85% specificity and 75% accuracy. The three-SNP predictive score was then validated in two independent cohorts of Thai and Malaysian β0-thalassemia/HbE patients with comparable specificity and accuracy. The SNP risk score could be used for prediction of clinical severity for Southeast Asia β0-thalassemia/HbE population.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  14. Fulltext Hemoglobin A2 and Heterogeneous Diagnostic Relevance Observed in Eight New Variants of the Delta Globin Gene
    Mahmud N, Maffei M, Mogni M, Forni GL, Pinto VM, Barberio G, et al.
    Genes (Basel), 2021 11 19;12(11).
    PMID: 34828427 DOI: 10.3390/genes12111821
    BACKGROUND: Hemoglobin A (Hb A) (α2β2) in the normal adult subject constitutes 96-98% of hemoglobin, and Hb F is normally less than 1%, while for hemoglobin A2 (Hb A2) (α2δ2), the normal reference values are between 2.0 and 3.3%. It is important to evaluate the presence of possible delta gene mutations in a population at high risk for globin gene defects in order to correctly diagnose the β-thalassemia carrier.

    METHODS: The most used methods for the quantification of Hb A2 are based on automated high performance liquid chromatography (HPLC) or capillary electrophoresis (CE). In particular Hb analyses were performed by HPLC on three dedicated devices. DNA analyses were performed according to local standard protocols.

    RESULTS: Here, we described eight new δ-globin gene variants discovered and characterized in some laboratories in Northern Italy in recent years. These new variants were added to the many already known Hb A2 variants that were found with an estimated frequency of about 1-2% during the screening tests in our laboratories.

    CONCLUSIONS: The knowledge recognition of the delta variant on Hb analysis and accurate molecular characterization is crucial to provide an accurate definitive thalassemia diagnosis, particularly in young subjects who would like to ask for a prenatal diagnosis or preimplantation genetic diagnosis.

    Matched MeSH terms: beta-Thalassemia/diagnosis
  15. Molecular basis of beta thalassemia in the south of Thailand
    Laosombat V, Fucharoen SP, Panich V, Fucharoen G, Wongchanchailert M, Sriroongrueng W, et al.
    Am J Hematol, 1992 Nov;41(3):194-8.
    PMID: 1415194
    A total of 103 beta thalassemia genes from 78 children (45 with Hb E/beta thalassemia, 8 with beta thalassemia heterozygotes, and 25 with homozygous beta thalassemia) were analyzed using dot-blot hybridization of the polymerase chain reaction-amplified DNA and direct DNA sequencing. Nine mutations were characterized in 98/103 (95%) of beta thalassemia alleles, of which six (a 4 bp deletion in codons 41-42, a G-C transition at position 5 of IVS-1, A-G transition at codon 19, an A-T transition at codon 17, an A-G transition at position -28 upstream of the beta globin gene, a G-T transition at position 1 of IVS-1), accounted for 92%. The spectrum of beta thalassemia mutations in Chinese Thai is similar to that reported among the Chinese from other parts of the world. The distribution of beta thalassemia mutations in Muslim Thai is similar to that reported among Malaysians. The most common beta thalassemia mutation in Thai and Chinese Thai patients is the frameshift mutation at codons 41-42, in comparison with the Muslim Thai in whom the G-C transition at position 5 of the IVS-1 mutation predominates. The heterogeneity of molecular defects causing beta thalassemia should aid in the planning of a prenatal diagnosis program for beta thalassemia in the South of Thailand.
    Matched MeSH terms: beta-Thalassemia/diagnosis
  16. An assessment of three noncommercial DNA extraction methods from dried blood spots for beta-thalassaemia mutation identification
    Karthipan SN, George E, Jameela S, Lim WF, Teh LK, Lee TY, et al.
    Int J Lab Hematol, 2011 Oct;33(5):540-4.
    PMID: 21884505 DOI: 10.1111/j.1751-553X.2011.01304.x
    Dried blood spots (DBS) are currently the recommended sample collection method for newborn screening programmes in America. Early diagnosis of beta-thalassaemia screening is essential as it provides an added advantage especially in sickle cell disease. Beta-thalassaemia frequency is high in many poor countries, and the cost of using commercial DNA extraction kits can be prohibitive. Our study assessed three methods that use minimal reagents and materials to extract DNA from DBS for beta-thalassaemia identification.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  17. [Simple and rapid analysis of beta-thalassemia mutation by sequence-specific amplification]
    Harano K, Harano T
    Rinsho Byori, 2013 Mar;61(3):217-23.
    PMID: 23785790
    This study was done to detect and diagnose beta-thalassemia (beta-Thal) gene quickly. We applied sequence specific Amplification (SSA) method to the analysis. 13 kinds of beta-Thal and two kinds of hemoglobin variants were able to detect under the same PCR condition. These mutations were found frequently in ten countries of Asian region (the southern part of China, Vietnam, Cambodia, Thailand, Myanmar, Malaysia, Singapore, Indonesia, Pakistan, India), and 15 kinds in total (-28CapA-->G, CD5-CT, CD8/9+-G, CD15G-->A, CD17A-->T, IVSI-1G-->T, CD41/42-4del, CD16-C, CD26G-->A(betaE), IVSI-5G-->C, CD35C-->A, CD71/72 +A, CD6A-->T (betaS), -619del, IVSII-654C-->T). More than 80% of patients are included in these mutations. To make the reagents a kit, the procedure became simple and rapid. DNA was extracted by salting out method. The PCR product was detected by polyacrylamide gel electrophoresis and silver staining. The confirmation of the variant was done by the PCR-direct sequencing method. It took approximately six hours for PCR reaction, electrophoresis and staining. This method made us to detect and diagnose beta-Thal in one day.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  18. HbA2 levels in normal, beta-thalassaemia and haemoglobin E carriers by capillary electrophoresis
    Hafiza A, Malisa MY, Khirotdin RD, Azlin I, Azma Z, Thong MC, et al.
    Malays J Pathol, 2012 Dec;34(2):161-4.
    PMID: 23424780
    The capillary electrophoresis (CE) is a new system that utilizes the principle of electrokinetic separation of molecules in eight electrolyte buffer-filled silica capillaries. In this study, we established the normal ranges of haemoglobin A2 (HbA2) and haemoglobin F (HbF) levels for normal individuals using this system and also the HbA2 level in beta thalassaemia and haemoglobin E (HbE) individuals.
    Matched MeSH terms: beta-Thalassemia/diagnosis
  19. Beta-thalassaemia mutations in west Malaysia: a new thalassaemia clinical score system
    George E
    Ann Acad Med Singap, 1994 Jan;23(1):89-93.
    PMID: 7514384
    The clinical severity of the mutations causing beta-thalassaemia in West Malaysia is presented. Thalassaemia clinical scores (Thal CS), a scoring system, has been formulated to predict clinical severity. It is the type of beta-thalassaemia mutation present that decides on the clinical phenotype. The most severe beta-thalassaemia mutation is assigned a score of 4. A score of 8 indicates a severe thalassaemia phenotype. Alpha-thalassaemia, increased synthesis of Hb F, and glucose-6-phosphate deficiency may ameliorate the clinical condition at phenotype level, and the co-inheritance of hereditary ovalocytosis aggravates it.
    Matched MeSH terms: beta-Thalassemia/diagnosis*
  20. Fulltext Spectrum of beta-thalassaemia mutations in transfusion dependent thalassaemia patients: practical implications in prenatal diagnosis
    George E, George R, Ariffin WA, Mokhtar AB, Azman ZA, Sivagengei K
    Med J Malaysia, 1993 Sep;48(3):325-9.
    PMID: 8183146
    The study concerned the identification of the beta-thalassaemia mutations that were present in 24 patients with beta-thalassaemia major who were transfusion dependent. The application of a modified polymerase chain reaction, the amplification refractory system (ARMS) was found to be an effective and rapid method for the identification of the beta-thalassaemia mutations. Six different mutations were detected. Seventy five percent of the patients were Chinese-Malaysians and showed the commonly occurring anomalies: 1. frameshift codon 41 and 42 (-TCTT); 2. the C to T substitution at position 654 of intron 2 (IVS-2); 3. the mutation at position -28(A to G); and the nonsense mutation A to T at codon 17. In the Malays, the common mutations seen were: 1. the G to C mutation at position 5 of IVS-1; 2. the G to T mutation at position 1 of intron 1 (IVS-1); and the A to T at codon 17. The delineation of the specific mutations present will enable effective prenatal diagnosis for beta-thalassaemia to be instituted.
    Matched MeSH terms: beta-Thalassemia/diagnosis
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