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  1. Fulltext A holistic approach to education programs in thalassemia for a multi-ethnic population: consideration of perspectives, attitudes, and perceived needs
    Wong LP, George E, Tan JA
    J Community Genet, 2011 Jun;2(2):71-9.
    PMID: 22109791 DOI: 10.1007/s12687-011-0039-z
    Hemoglobin disorders which include thalassemias are the most common heritable disorders. Effective treatment is available, and these disorders can be avoided as identification of carriers is achievable using simple hematological tests. An in-depth understanding of the awareness, attitudes, perceptions, and screening reservations towards thalassemia is necessary, as Malaysia has a multi-ethnic population with different religious beliefs. A total of 13 focus group discussions (70 participants) with members of the general lay public were conducted between November 2008 and January 2009. Lack of knowledge and understanding about thalassemia leads to general confusions over differences between thalassemia carriers and thalassemia major, inheritance patterns, and the physical and psychologically impact of the disorder in affected individuals and their families. Although most of the participants have not been tested for thalassemia, a large majority expressed willingness to be screened. Views on prenatal diagnosis and termination of fetuses with thalassemia major received mixed opinions from participants with different religions and practices. Perceived stigma and discrimination attached to being a carrier emerged as a vital topic in some group discussions where disparity in the answers exhibited differences in levels of participants' literacy and ethnic origins. The two most common needs identified from the discussion were information and screening facilities. Participants' interest in knowing the severity of the disease and assessing their risk of getting the disorder may imply the health belief model as a possible means of predicting thalassemia public screening services. Findings provide valuable insights for the development of more effective educational, screening, and prenatal diagnostic services in the multi-ethnic Asian society.
  2. Fulltext A novel gap-PCR with high resolution melting analysis for the detection of α-thalassaemia Southeast Asian and Filipino β°-thalassaemia deletion
    Kho SL, Chua KH, George E, Tan JA
    Sci Rep, 2015;5:13937.
    PMID: 26365497 DOI: 10.1038/srep13937
    Homozygosity for the α-thalassaemia Southeast Asian (α-SEA) and Filipino β°-thalassaemia (β-FIL) deletions can cause serious complications leading to foetal death or life-long blood transfusions. A rapid and accurate molecular detection assay is essential in populations where the deletions are common. In this study, gap-polymerase chain reaction (PCR) with high resolution melting (HRM) analysis was developed to detect both the large deletions. Melting curves at 86.9 ± 0.1 °C were generated by normal individuals without the α-SEA deletion, 84.7 ± 0.1 °C by homozygous α-SEA deletion individuals and two melting curves at 84.7 ± 0.1 °C and 86.9 ± 0.1 °C by α-SEA deletion carriers. Normal individuals without the β-FIL deletion produce amplicons with a melting temperature (Tm) at 74.6 ± 0.1 °C, homozygous β-FIL individuals produce amplicons with Tm at 73.6 ± 0.1 °C and heterozygous β-FIL individuals generate two amplicons with Tm at 73.6 ± 0.1 °C and 74.6 ± 0.1 °C. Evaluation using blinded tests on 220 DNA samples showed 100% sensitivity and specificity. The developed assays are sensitive and specific for rapid molecular and prenatal diagnosis for the α-SEA and β-FIL deletions.
  3. Fulltext An alternative method for rapid detection of alpha thalassaemia variants in Malaysia using droplet digital PCR
    Lee, Tze Yan, George, Elizabeth, Mei, I Lai, Ramachandran, Vasudevan, Tan, Jin Ai Mary Anne, Lai, Kuan Teh, et al.
    Journal of Biomedical and Clinical Sciences, 2017;2(202):54-56.
    MyJurnal
    Globally, α-thalassaemia is a highly prevalent disease. In Malaysia, this disorder is a well-known public health problem [1]. The three most common deletional α-thalassaemia found in this region include --SEA deletion, -α3.7 and -α4.2 deletions [2]. The prevalence rate of triplication alpha cases such as αααanti3.7 and αααanti4.2 is unknown in Malaysia although it plays a pivotal role in exacerbating the clinical phenotypes in beta thalassaemia carriers [3]. Therefore, the purpose of this study was to design an assay for the detection of triplications and common deletional alpha thalassaemia using droplet digital PCR (ddPCR). Copy number changes were analysed using Quanta-SoftTM software version 1.6.6 after performing ddPCR. Sensitivity and validation analysis were also performed on the DNA samples. The changes in copy number changes (common deletions, duplications and triplications) in the alpha globin gene has been quantitatively detected using ddPCR. For the samples validation as determined by ddPCR, the mean copy number values for αα/αα are 2.0275±0.0177 (HS-40), 1.8175±0.0389 (HBA2), 2.0450±0.0848 (HB 3.7), 2.0050±0.0000 (HBA1). For -α3.7 /--SEA, the mean copy number values are 2.0225±0.2180 (HS-40), 0.9325±0.1213 (HBA2), 0 (HB 3.7), 0.9984±0.1333 (HBA1). As for –α4.2 /--SEA, the mean copy number values are 1.9350 (HS-40), 0 (HBA2), 0.7945 (HB 3.7), 0.8480 (HBA1). The mean copy number values for --SEA/αα samples are 1.9067±0.1327 (HS-40), 0.8164±0.0364 (HBA2), 0.8920±0.0434 (HB 3.7), 0.9148±0.0338 (HBA1) respectively. This study has found that the use of ddPCR is convenient as it allows direct quantification without the requirement of a calibration curve unlike qPCR [4]. Secondly, this study also showed that ddPCR is accurate and precise in the detection of alpha thalassaemia deletions and triplications based on the gene dosages using absolute quantification. In addition, the non-requirement of post-PCR work has minimised the risk of PCR carryover contamination. Thirdly, ddPCR saves time with less turnaround time and minimise the labour work required as compared to techniques such as MLPA which requires DNA denaturation and hybridisation reaction on day 1 while ligation and PCR reaction on day 2. Fourthly, this study found that the detection of α-thalassaemia using ddPCR is sensitive. DNA samples with low concentration as low as 1 ng were able to be detected for α-thalassaemia using ddPCR. The ability to detect minute amount of DNA concentration is crucial particularly in the diagnosing of the lethal HbH hydrops foetalis during the neonatal stage in α-thalassaemia. In conclusion, this is an alternative method (ddPCR) that can be employed for rapid detection of alpha thalassaemia variants in Malaysia.
  4. Fulltext Anaemia in type 2 diabetes mellitus (T2DM) patients in Hospital Putrajaya
    Thambiah CS, Samsudin IN, George E, Ranjit LK, Saat NS, Hussein Z, et al.
    Malaysian Journal of Medicine and Health Sciences, 2015;11(1):49-62.
    MyJurnal
    Patients with diabetes have an earlier onset and increased severity of anaemia compared to those with similar degree of renal impairment from other causes. Anaemia is associated with an increased risk of vascular complications. In this study, we determined the prevalence of anaemia in T2DM patients and its association with sociodemographic, clinical and laboratory parameters in an endocrine tertiary hospital in Malaysia. This was a cross-sectional study using retrospective electronic data from January 2011 to December 2013 of 165 T2DM patients in Hospital Putrajaya. Data was analysed using IBM SPSS Statistics version 21.0 for Windows. The prevalence of anaemia was 39.4% and majority had normocytic normochromic (80%), mild (58.5%) anaemia. Majority were Malays (73.9%), aged below 60 with comparable gender percentage and long-standing, poorly-controlled DM [median fasting blood sugar (FBS) 8mmol/L; glycated haemoglobin (HbA1c) 7.9%]. Using the KDIGO chronic kidney disease (CKD) staging system, 86% of these patients were in stages 3-5. Anaemic patients had a significantly higher serum urea, creatinine and a lower FBS, estimated glomerular filtration rate (eGFR) compared to non-anaemic patients. Anaemic patients with diabetic nephropathy had a significantly lower haemoglobin (Hb) compared to those without this complication (p=0.022). The sensitivity and specificity at a cut-off eGFR value of 38.3 ml/min/1.73 m2 (maximum Youden index = 0.462) was 66.7% and 79.5%, respectively to discriminate mild from moderate anaemia. This study shows that anaemia is already present in T2DM patients in Hospital Putrajaya at initial presentation to the specialist outpatient clinic and is significantly associated with CKD. Hence, it emphasises the obligatory need for routine and follow-up full blood count monitoring in T2DM patients in primary care as well as tertiary settings in Malaysia to enable early detection and aggressive correction of anaemia in preventing further complications.

    Study site: endocrine clinic, Hospital Putrajaya
  5. Fulltext Awareness of glycosylated haemoglobin (hba1c) among type 2 diabetes mellitus patients in Hospital Putrajaya
    Intan Nureslyna Samsudin, Thambiah, Subashini C., Wan Mohamad Asyraf Wan Mohammed Ayub, Cheng, Ng Wan, Zanariah Hussein, Nurain Mohd Noor, et al.
    Malaysian Journal of Medicine and Health Sciences, 2015;11(2):1-8.
    MyJurnal
    The glycosylated haemoglobin (HbA1c) test is the most widely accepted laboratory test for evaluating long term glycaemic control. Patient’s understanding of HbA1c can lead to better glycaemic control. This study is aimed to determine the awareness and level of understanding of HbA1c among type 2 DM patients and its association with glycaemic control. A cross-sectional descriptive study among Type 2 DM patients undergoing routine follow up in an endocrine clinic of a tertiary centre in Malaysia. Patients were invited to answer a validated questionnaire which assessed their awareness and understanding of HbA1c. Their last HbA1c results were retrieved from the laboratory information system. A total of 92 participants were recruited. Fifty-six (60.9%) were aware of the term HbA1c. Fifty percent were categorised as having good HbA1c understanding, with age, monthly income and level of education being the factors associated with understanding. No significant association was noted between HbA1c understanding and glycaemic control, although more patients with good HbA1c understanding had achieved the target glycaemic control compared to those with poor understanding. The level of HbA1c awareness and understanding was acceptable. Factors associated with understanding were age, income and level of education. Continuing efforts however, must be made to improve patients understanding of their disease and clinical disease biomarkers.
  6. Characterisation and confirmation of rare beta-thalassaemia mutations in the Malay, Chinese and Indian ethnic groups in Malaysia
    Tan JA, Chin PS, Wong YC, Tan KL, Chan LL, George E
    Pathology, 2006 Oct;38(5):437-41.
    PMID: 17008283
    In Malaysia, about 4.5% of the Malay and Chinese populations are heterozygous carriers of beta-thalassaemia. The initial identification of rare beta-globin gene mutations by genomic sequencing will allow the development of simpler and cost-effective PCR-based techniques to complement the existing amplification refractory mutation system (ARMS) and gap-PCR used for the identification of beta-thalassaemia mutations.
  7. Fulltext Co-inheritance of Southeast Asian ovalocytosis and Hb e: does it affect the red blood cells indices?
    Riahi, Shahrzard, Mei, I Lai, George, Elizabeth, Ida Marhainis Isahak, Faridah Idris, Sabariah Md Noor
    Journal of Biomedical and Clinical Sciences, 2017;2(202):44-46.
    MyJurnal
    Complete blood count (CBC) is used broadly to screen individual's general health status. Some inherited red blood cell (RBC) disorders influence the RBC parameters. Mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) are amongst the important RBC parameters used in thalassaemia-haemoglobinopathy screening [1-2]. Globin chain disorders and Southeast Asian Ovalocytosis (SAO) are common RBC disorders in Southeast Asian countries [3]. We evaluated the RBC parameters in patients with Hb E and those with SAO co-inheritance.

    A total of 33 from 1500 Malay patient’s samples that were sent for thalassaemia-haemoglobinopathies screening in Hospital Kuala Lumpur (HKL) were identified and consented (30 cases with Hb E and 3 cases with co-inheritance of Hb E and SAO). The inclusion criteria were Malay patients with MCV and MCH levels less than 78 fL and 27 pg respectively with presence of oval and stomatocytic RBCs in the peripheral blood film. DNA extraction was performed in samples suspected of having co-inheritance of SAO and Hb E. Primers 198 and 199 (AIT biotech Pte Ltd. Singapore) were designed for SAO detection [4], [5]. Hb E mutation was detected using ARMS PCR [6].

    SAO was characterised by presence of an in frame 27bp deletion in exon 11 of the band 3 gene. A band of 175bp was observed in normal subjects and two bands, 175bp and 148bp were observed in heterozygous SAO subjects (Fig. 1).
  8. Fulltext Correlation of BACH1 and Hemoglobin E/Beta-Thalassemia Globin Expression
    Lee TY, Muniandy L, Teh LK, Abdullah M, George E, Sathar J, et al.
    Turk J Haematol, 2016 Mar 05;33(1):15-20.
    PMID: 26377036 DOI: 10.4274/tjh.2014.0197
    The diverse clinical phenotype of hemoglobin E (HbE)/β-thalassemia has not only confounded clinicians in matters of patient management but has also led scientists to investigate the complex mechanisms involved in maintaining the delicate red cell environment where, even with apparent similarities of α- and β-globin genotypes, the phenotype tells a different story. The BTB and CNC homology 1 (BACH1) protein is known to regulate α- and β-globin gene transcriptions during the terminal differentiation of erythroid cells. With the mutations involved in HbE/β-thalassemia disorder, we studied the role of BACH1 in compensating for the globin chain imbalance, albeit for fine-tuning purposes.
  9. Fulltext DNA studies are necessary for accurate patient diagnosis in compound heterozygosity for Hb Adana (HBA2:c.179>A) with deletional or nondeletional α-thalassaemia
    Tan JA, Kho SL, Ngim CF, Chua KH, Goh AS, Yeoh SL, et al.
    Sci Rep, 2016 06 08;6:26994.
    PMID: 27271331 DOI: 10.1038/srep26994
    Haemoglobin (Hb) Adana (HBA2:c.179>A) interacts with deletional and nondeletional α-thalassaemia mutations to produce HbH disorders with varying clinical manifestations from asymptomatic to severe anaemia with significant hepatosplenomegaly. Hb Adana carriers are generally asymptomatic and haemoglobin subtyping is unable to detect this highly unstable α-haemoglobin variant. This study identified 13 patients with compound heterozygosity for Hb Adana with either the 3.7 kb gene deletion (-α(3.7)), Hb Constant Spring (HbCS) (HBA2:c.427T>C) or Hb Paksé (HBA2:429A>T). Multiplex Amplification Refractory Mutation System was used for the detection of five deletional and six nondeletional α-thalassaemia mutations. Duplex-PCR was used to confirm Hb Paksé and HbCS. Results showed 84.6% of the Hb Adana patients were Malays. Using DNA studies, compound heterozygosity for Hb Adana and HbCS (α(codon 59)α/α(CS)α) was confirmed in 11 patients. A novel point in this investigation was that DNA studies confirmed Hb Paksé for the first time in a Malaysian patient (α(codon 59)α/α(Paksé)α) after nine years of being misdiagnosis with Hb Adana and HbCS (α(codon 59)α/α(CS)α). Thus, the reliance on haematology studies and Hb subtyping to detect Hb variants is inadequate in countries where thalassaemia is prevalent and caused by a wide spectrum of mutations.
  10. Editorial. WHO in Malaysia
    George E
    Family Practitioner, 1988;11(1):7-10.
  11. Fulltext Effect of transfusion, iron chelation and splenectomy therapies in HbE/β-thalassaemia individuals in Malaysia
    Lim, Wai Feng, Muniandi, Logeswaran, George, Elizabeth, Sathar, Jameela, Teh, Lai Kuan, Lai, Mei I.
    Journal of Biomedical and Clinical Sciences, 2017;2(202):60-61.
    MyJurnal
    HbE/β-thalassaemia is a compound heterozygous mutation with a vast clinical phenotype [1]. To improve quality of life, HbE/β-thalassaemia individuals receive different treatment strategies, either individually or in combination with therapy(ies), including blood transfusion, iron chelation and splenectomy [2-3]. Thus far, there are limited studies conducted regarding the effect of treatments in HbE/β-thalassaemia individuals. We hereby investigated the effect of treatments with respect to red blood cell indices, haemoglobin subtypes and gene expressions among 30 HbE/beta-thalassaemia individuals. Statistical analyses were carried out using SPSS 17.0. As compared to single therapy (transfused only individuals) and double therapies (transfused-chelated only individuals), individuals receiving triple therapies (transfused-chelated-splenectomised individuals) showed significantly high mean cell volume (MCV), mean cell haemoglobin (MCH) and reticulocytes count (Fig.1).

    These findings suggest that triple therapies are the most effective in ameliorating the severity of the disease in terms of microcytosis and hypochromia [3-5]. The high reticulocyte count in triple therapies also allows the bone marrow to actively produce red blood cells suggesting that these therapies have clinical benefits by suppressing the ineffective erythropoiesis and improving the erythropoietic environment significantly among HbE/β-thalassaemia individuals in our studied group [6-7].

    The effectiveness of these treatments is different among each HbE/β-thalassaemia individual whereby clinical variabilities among them could be a contributing factor. Triple therapies giving the best advantage to the HbE/β-thalassaemia patient in this study.
  12. Fulltext Evaluation of red blood cell indices related disorders among eligible blood donors at the Universiti Putra Malaysia (UPM)
    Riahi S, Mei IL, Idris FB, George E, Noor SM
    Southeast Asian J. Trop. Med. Public Health, 2015 Sep;46(5):911-7.
    PMID: 26863862
    Pre-donation screening declarations and hemoglobin (Hb) testing are measures used to determine the quality of donated blood. The copper sulphate (CuSo4) method used to screen for blood abnormalities can give inaccurate results if strict quality control is not applied. Blood donors who are carriers of thalassemia and those with mild iron deficiency anemia (IDA) are usually asymptomatic and frequently missed at blood donation. The aim of this study was to evaluate the red blood cell (RBC) indices related disorders among blood donors who were deemed qualified to donate blood after screening with CuSo4 method. One hundred fifty-eight volunteer blood donors at the Universiti Putra Malaysia (UPM), who had passed the CuSo4 screening method, were recruited for this study. Their bloods specimens were examined with a complete blood count. Subjects with a low mean corpuscular hemoglobin (MCH) level were examined further by checking a serum ferritin level, Hb quantification, and molecular analysis to examine for common RBC disorders. Fourteen point six percent of subjects had a low Hb level, two (1.3%) had IDA and four (2.5%) had thalassemia or some other hemoglobinopathy. Using a MCH level < 27 pg as a cut-off point, 58 subjects (36.7%) had suspected IDA, thalassemia or some other hemoglobinopathy. Eight point nine percent of subjects with a normal Hb level had thalassemia, and 3.8% had IDA. Malaysia has a high prevalence of thalassemia and other hemoglobinopathies. Pre-donation accurate screening is crucial to protect the quality of blood transfusion products. Public education regarding RBC disorders especially among blood donors is important.
  13. Fulltext Generation and characterisation of human umbilical cord derived mesenchymal stem cells by explant method
    Yusoff Z, Maqbool M, George E, Hassan R, Ramasamy R
    Med J Malaysia, 2016 Jun;71(3):105-10.
    PMID: 27495882 MyJurnal
    Mesenchymal stem cells (MSCs) derived from human umbilical cord (UC) have been considered as an important tool for treating various malignancies, tissue repair and organ regeneration. Umbilical cord-derived mesenchymal stem cells (UC-MSCs) are better alternative to MSCs that derived from bone marrow (BM-MSCs) as they are regarded as medical waste with little ethical concern for research and easily culture-expanded. In this present study, the foetal distal end of human UC was utilised to generate MSC by explant method. Upon in vitro culture, adherent cells with fibroblastic morphology were generated with rapid growth kinetics. Under the respective inductive conditions, these cells were capable of differentiating into adipocytes and osteocytes; express an array of standard MSC's surface markers CD29, CD73, CD90, CD106 and MHC-class I. Further assessment of immunosuppression activity revealed that MSCs generated from UC had profoundly inhibited the proliferation of mitogen-activated T lymphocytes in a dosedependent manner. The current laboratory findings have reinforced the application of explant method to generate UCMSCs thus, exploring an ideal platform to fulfil the increasing demand of MSCs for research and potential clinical use.
  14. Fulltext Genetic variants in HBS1L-MYB rs9399137 and rs11759553 associated with elevated HbF levels among Filipino β°-deletion carriers
    Lai, Kuan Teh, Koh, Sam Yu, Shi, Min Chua, George, Elizabeth, Mei, I Lai, Wong, Lily
    Journal of Biomedical and Clinical Sciences, 2017;2(202):28-29.
    MyJurnal
    In Malaysia, Sabah population constitutes the most number of β-thalassaemia cases ranging from asymptomatic to transfusion dependent. Filipino β°-deletion has been reported as the predominant mutation in Sabah [1]. Despite having the same primary mutation, co-inheritance of genetic variants at HbF quantitative trait loci of HBS1L-MYB intergenic region may cause variability in clinical features by affecting the haemoglobin (Hb) subtypes level, especially HbF. Study suggested that MYB would activate γ-globin repressor gene directly and subsequently initiate the molecular HbF repression mechanisms. Polymorphisms within HBS1L-MYB intergenic region would inhibit binding of transcription factor on MYB and leading to elevation of HbF levels [2]. This can act as an ameliorating factor in the clinical presentation of β-thalassaemia patients [3]. This study aimed to elucidate the association of Hb subtypes levels with three HBS1L-MYB variants among 134 Filipino β°-deletion carriers. PCR-RFLP analysis was done for HBSIL-MYB rs4895441 (A→G) while tetra-primers ARMS PCR analysis was done for HBSIL-MYB rs9399137 (T→C) and rs11759553 (A→T) (Fig.1).
  15. Fulltext Genotype-phenotype diversity of beta-thalassemia in Malaysia: treatment options and emerging therapies
    George E, Ann TJ
    Med J Malaysia, 2010 Dec;65(4):256-60.
    PMID: 21901940 MyJurnal
    The haemoglobinopathies and thalassemias represent the most common inherited monogenic disorders in the world. Beta-thalassaemia major is an ongoing public health problem in Malaysia. Prior to 2004, the country had no national policy for screening and registry for thalassemia. In the absence of a national audit, the true figure of the extent of thalassemia in the Malaysian population was largely presumptive from micro-mapping studies from various research workers in the country. The estimated carrier rate for beta-thalassemia in Malaysia is 3.5-4%. There were 4768 transfusion dependent thalassemia major patients as of May 2010 (Data from National Thalassemia Registry).
  16. Fulltext Haemoglobin Lepore in a Malay family: a case report
    Pasangna J, George E, Nagaratnam M
    Malays J Pathol, 2005 Jun;27(1):33-7.
    PMID: 16676691
    A 2-year-old Malay boy was brought to the University Malaya Medical Centre for thalassaemia screening. Physical examination revealed thalassaemia facies, pallor, mild jaundice, hepatomegaly and splenomegaly. Laboratory investigations on the patient including studies on the parents lead to a presumptive diagnosis of homozygous Haemoglobin Lepore (Hb Lepore). The aim of this paper is to increase awareness of this rare disorder, this being the first case documented in Malaysia in a Malay. The case also demonstrates the need for this disorder to be included in the differential diagnosis of patients presenting clinically like thalassemia intermedia or thalassemia major. Accurate diagnosis would provide information necessary for prenatal diagnosis, proper clinical management and genetic counseling. The clinical, haematological and laboratory features of this disorder are discussed in this paper.
  17. Fulltext High prevalence of alpha- and beta-thalassemia in the Kadazandusuns in East Malaysia: challenges in providing effective health care for an indigenous group
    Tan JA, Lee PC, Wee YC, Tan KL, Mahali NF, George E, et al.
    J Biomed Biotechnol, 2010;2010.
    PMID: 20871816 DOI: 10.1155/2010/706872
    Thalassemia can lead to severe transfusion-dependent anemia, and it is the most common genetic disorder in Malaysia. This paper aims to determine the prevalence of thalassemia in the Kadazandusuns, the largest indigenous group in Sabah, East Malaysia. α- and β-thalassemia were confirmed in 33.6% and 12.8%, of the individuals studied respectively. The high prevalence of α- and β-thalassemia in the Kadazandusuns indicates that thalassemia screening, genetic counseling, and prenatal diagnosis should be included as part of their healthcare system. This preliminary paper serves as a baseline for further investigations into the health and genetic defects of the major indigenous population in Sabah, East Malaysia.
  18. Fulltext High throughput molecular confirmation of β-thalassemia mutations using novel TaqMan probes
    Kho SL, Chua KH, George E, Tan JA
    Sensors (Basel), 2013;13(2):2506-14.
    PMID: 23429513 DOI: 10.3390/s130202506
    β-Thalassemia is a public health problem where 4.5% of Malaysians are β-thalassemia carriers. The genetic disorder is caused by defects in the β-globin gene complex which lead to reduced or complete absence of β-globin chain synthesis. Five TaqMan genotyping assays were designed and developed to detect the common β-thalassemia mutations in Malaysian Malays. The assays were evaluated with 219 "blinded" DNA samples and the results showed 100% sensitivity and specificity. The in-house designed TaqMan genotyping assays were found to be cost- and time-effective for characterization of β-thalassemia mutations in the Malaysian population. 
  19. Human mesenchymal stem cells protect neutrophils from serum-deprived cell death
    Maqbool M, Vidyadaran S, George E, Ramasamy R
    Cell Biol Int, 2011 Dec;35(12):1247-51.
    PMID: 21649586 DOI: 10.1042/CBI20110070
    We have previously shown that human MSC (mesenchymal stem cells) inhibit the proliferation of most of the immune cells. However, there are innate immune cells such as neutrophils and other PMN (polymorphonuclear) cells that do not require an extensive proliferation prior to their effector function. In this study, the effect of MSC on neutrophils in the presence of complete and serum-deprived culture media was investigated. In the presence of MSC, the viability of neutrophils increase as measured in 24 h of incubation at various supplementation of serum concentration. We have utilized Annexin V and PI (propidium iodide) staining to confirm whether the enhancement of neutrophil's viability is due to a reduction in PCD (programmed cell death). MSC significantly rescue neutrophils from apoptosis at 1, 5 and 10% of FBS (fetal bovine serum) supplementation. The fractions of viable and dead cells were increased and decreased respectively in the presence of MSC. Our results indicate MSC rescue neutrophils from nutrient- or serum-deprived cell death. However, whether this effect is exerted through a specific signalling pathway or confining neutrophils in resting state by MSC requires further investigation.
  20. Interaction of Hb South Florida (codon 1; GTG-->ATG) and HbE, with beta-thalassemia (IVS1-1; G-->A): expression of different clinical phenotypes
    Tan JA, Tan KL, Omar KZ, Chan LL, Wee YC, George E
    Eur J Pediatr, 2009 Sep;168(9):1049-54.
    PMID: 19034506 DOI: 10.1007/s00431-008-0877-9
    INTRODUCTION: Interactions of different hemoglobin variants with thalassemia alleles can result in various clinical phenotypes. HbE-beta-thalassemia generally manifests with severe anemia where individuals exhibit beta-thalassemia major with regular blood transfusions or beta-thalassemia intermedia with periodic blood transfusions. This study presents a unique Malay family with three beta-globin gene defects-HbE, Hb South Florida, and IVS1-1 (G-->A).

    MATERIALS AND METHODS: HbE activates a cryptic splice site that produces non-functional mRNAs. Hb South Florida is a rare beta-hemoglobin variant, and its interactions with other beta-thalassemia alleles have not been reported. IVS1-1 is a Mediterranean mutation that affects mRNA processing giving rise to beta(o)-thalassemia.

    RESULTS AND DISCUSSION: Fifteen mutations along the beta-globin gene complex were analyzed using the amplification refractory mutation system. Hb South Florida was identified by direct sequencing using genomic DNA.

    CONCLUSION: The affected child with HbE/IVS1-1 produced a beta-thalassemia major phenotype. Compound heterozygosity for Hb South Florida/IVS1-1 produced a beta-thalassemia carrier phenotype in the mother.

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