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.
Beta-thalassemia in West Malaysia is caused by 14 molecular defects with differing clinical severity. In Chinese patients from West Malaysia, the main beta-thalassemia mutations seen were (a) a 4 base pair-TCTT deletion in codon 41-42 [frameshift mutation (FSC 41-42)]; (b) a C to T substitution at the second intervening sequence (IVS2-654); (c) an A to G substitution in the TATA box [-28 (A to G)], and (d) an A to T substitution in codon 17[17 A to T]. In the Malays, the main mutations seen were (a) a G to C in nucleotide 5 at the intervening sequence I [IVS1-5 (G to C)]; (b) G to T substitution in nucleotide I at the intervening sequence I [IVS1-1 (G to T)]; (c) a A to T substitution in codon 17 (17 A to T); (d) removal of C from codon 35 [codon 35 (-C)], and (e) a 4 base pairs-TCTT deletion in codon 41-42 [frameshift mutation (FSC 41-42)]. A scoring system (Tha1 CS) has been formulated to predict clinical severity. It is the type of beta-thalassemia mutation present that decides on the clinical phenotype. The most severe beta-thalassemia mutation is assigned a score of 4. A score of 8 indicates severe thalassemia.
Hereditary haemolytic anaemias have been found to be a significant cause of haemolytic disease in West Malaysia. This paper reports a micromapping study of 916 healthy Malay males from June to August 1983 to determine the distribution of the relevant thalassaemia genes in West Malaysia. Beta thalassaemia trait was found in 2.18%, HbE 3.49% and alpha thal2 (alpha+) trait in 26%. Of the sixteen transfusion dependant Malay thalassaemic patients at the Paediatric Unit, National University of Malaysia, eight patients had HbE beta thalassaemia and the rest are beta thalassaemia major; these patients who are transfusion dependant receive inadequate treatment. Prevention is the only resort.
In the newborn the diagnosis of alpha thalassaemia trait is easier because of the presence of haemoglobin Bart's (Hb Bart's). Alpha thalassaemia is common in Southeast Asia. Malaysians are composed of the ethnic groups Malays, Chinese, Indians and Eurasians. Hb Bart's itself is not a simple inherited character but arises from genetically determined imbalance in the biosynthesis of alpha and non alpha chains. 58% of the cord blood samples tested showed raised levels of Hb Bart's. In the Chinese the most common cause of hereditary haemolytic anaemia is haemoglobin H and hydrops foetalis is seen. The rare occurrence of these syndromes in the Malays and Indians in spite of the presence of Hb Bart's indicates an altered expression of the alpha thalassaemia gene in these populations.
Beta (β)- thalassaemia is a public health problem in Malaysia. The carrier rate is estimated to be 4.5% by micro-mapping studies particularly among Malays who comprise 53.5% of the population in Malaysia. The common diagnostic method in Malaysia for mutation detection is by amplification refractory mutation system (ARMS). It allows single mutation detection in each reaction but is labour intensive and time consuming when many mutations need to be identified. The purpose of this study was to develop a diagnostic tool for effective mutation detection of beta thalassaemia in Malay patients and compare its efficacy with ARMS-PCR, the current method in use. Methods: Reverse dot blot hybridization (RDBH) technique was incorporated in the development of two strip assays [RDBH-Strip M(6) and RDBH-Strip C(6)] to identify common beta thalassaemia mutations in the Malays. The panels of selected mutations were based on the mutation frequencies in Malaysia reported in previous studies. RDBH-Strip M(6) was applied as step 1 and RDBH-Strip C(6) was applied as step 2 for unidentified mutations. The strips were validated with the gold standard method, ARMS- PCR. Results: One hundred and thirty seven Malay patients with 274 alleles were studied. In Step 1 mutation detection, 238 alleles (86.9%) were identified in 119 of patients by RDBH-Strip M(6). Step 2 resulted in a further detection of 20 alleles in another 10 patients by RDBH-Strip C(6). The combination of both strips resulted in the identification of 258 alleles in 129 (94.6%) of 137 Malay patients. The strip assays were 100% sensitive and specific when compared with ARMS-PCR method. Conclusion: Two strip assays utilising the RDBH technique were developed to identify common β-thalassaemia mutations in Malays. The RDBH Strip M(6) identified 86.9% of the mutations and the RDBH-Strip C (6) detected further 7.3% alleles. This two step strategy was found to be rapid and cost effective for the direct diagnosis of β-thalassaemia mutations in the Malays. The remaining unidentified mutations would require DNA sequencing. It can serve as a specific molecular diagnostic tool for effective diagnosis of
β-thalassaemia mutations in this ethnic group.
Monoclonal gammopathies result from an overproduction of a single abnormal clone of plasma cell
or B lymphocyte that produce an immunologically homogenous immunoglobulin (Ig) commonly referred to as paraprotein or monoclonal (M) protein. The circulating M-protein may consist of an intact immunoglobulin, the light chain only, or (rarely) the heavy chain only. The heavy chain is from one of the five immunoglobulin classes G, A, M, D or E, while the light chain is either kappa (κ) or lambda (λ) in type. Accurate detection and quantitation of monoclonal immunoglobulins is important for the diagnosis and management of monoclonal gammopathies. We report a case of a 71 year old lady with a history of chronic gastritis and recurrent lower respiratory tract infection whereby no specific diagnosis was made until a computed tomography (CT) guided lung biopsy and orogastroduodenoscopy (OGDS) 5 years later from the onset of initial symptoms revealed pulmonary and gastric amyloidosis, respectively.
Functional analysis of neutrophils requires isolation of these cells in the laboratory. Current isolation procedures are time consuming and can potentially activate the resting neutrophils. Thus, in this present study, we have optimised an existing laboratory protocol for human neutrophil isolation from peripheral blood. Twenty ml of blood samples were subjected to optimised density gradient separation and dextran sedimentation to obtain a pure population of neutrophils. The efficacy of the optimised manual post isolation of neutrophils was compared with pre isolation count performed by an automated haematology analyzer. The recovery of neutrophils via our optimised methods was 65.5% in comparison with neutrophils counts at pre-isolation. The morphological analysis of isolated neutrophils indicated the purity level more than 95% using Leishman staining. Our optimised laboratory procedures for neutrophils isolation successfully harvested neutrophils with good viability, purity and post recovery yield. This procedure provides an ideal platform to separate neutrophils for in vitro studies.
Serum ferritin concentration has been measured in pregnant women at their first antenatal visit. Results were analysed according to trimesters. With progression of the pregnancy there is a fall in serum ferritin concentrations. Haemoglobin and red cell indices cannot be used to predict iron status supplemental iron therapy raised the serum ferritin levels.
Hereditary stomatocytic ovalocytosis and haemoglobin E are two genes present in 3-5% of Malays. This is a report of a 22 year old Malay college student with homozygous haemoglobin E and hereditary stomatocytic ovalocytosis where the clinical effects seen were the result of the summation of these genes: he was asymptomatic, presenting with moderate jaundice, moderate hepatosplenomegaly, and a mild haemolytic anaemia.
Alpha thalassaemia is one of the haemoglobin disordersin which the carriers of alpha thalassaemia may have normal haemoglobin level and are eligible to donate blood which may bring complications. This study is to investigate the interaction of haematological parameter with α-globin genotypes among eligible blood donors. Materials & Methods: A cohort study with 270 eligible blood donors were analysed for red cell indices. Alpha-globin (α-globin) genotyping was performed for seven deletions, six point mutations and two triplications. Statistical analyses were performed to compare the α-globin genotypes with haematological data. Results: High prevalence of α-thalassaemia carriers (7.7%, 21/270) was found among blood donors. All of them did not show anaemic pictures with a normal Hb level (>12 gm/dl). Five genotypes were identified consisting of 249 αα/αα (92.2%), nine -α3.7/αα (3.3%), nine--SEA/αα (3.3%), two -α4.2/αα (0.7%) and one ααCS/αα (0.4%). Different α-globin genotypes showed a significant difference in RBC, MCV, MCH, MCHC, RDW, and Hct/Hb ratio (p
Management of Beta (β)-thalassaemia intermedia in contrast to β-thalassaemia major patients has no clear guidelines as to indicators of adequate transfusion. Regular blood transfusion suppresses bone marrow erythropoietic activity. Serum soluble transferrin receptor (sTfR) concentration is a marker for erythropoietic activity, with increased sTfR being associated with functional iron deficiency and increased erythropoietic activity. This study aimed to determine the use of sTfR as an indicator of adequate transfusion in adult β-thalassaemia intermedia patients. A cross-sectional study was conducted at Hospital Ampang, Malaysia, for six months. Patient group included six β-thalassaemia intermedia and 34 HbE-β-thalassaemia transfused patients. None of the patients were on regular monthly blood transfusions as in β-thalassaemia major. The control group comprised of 16 healthy subjects with normal haematological parameters. Haemoglobin (Hb) analysis, sTfR and ferritin assays were performed. Hb and HbA percentages (%) were found to be significantly lower in patients compared to the controls, while HbE%, HbF%, sTfR and ferritin were significantly higher in patients. An inverse relationship was found in the controls between HbF% with Hb (r = -0.515, p < 0.05) and HbA% (r = -0.534, p < 0.05). In patients, sTfR showed an inverse relationship with HbA% (r = -0.618, p = 0.000) and a positive correlation with HbE% (r = 0.418, p = 0.007) and HbF% (r = 0.469, p = 0.002). Multivariate analysis showed that HbA% (r = 2.875, p = 0.048), HbE% (r = 2.872, p = 0.020) and HbF% (r = 2.436, p = 0.013) best predicted sTfR independently in patients. Thus, sTfR is a useful marker for erythropoiesis. The elevated sTfR in these patients indicate that the transfusion regimen used was inadequate to suppress ineffective erythropoiesis. Hb levels may not be the best target for monitoring transfusion treatment in β-thalassaemia intermedia patients, but the use of sTfR is helpful in individualising transfusion regimens.
Patients with the Hb beta + [IVS 1-5 (G-->C)] clinically presented as beta-thalassaemia intermedia and remained asymptomatic in the absence of blood transfusions. With or without blood transfusions the patients were short and had moderate to marked thalassaemia facies. Children who received blood transfusions showed progressive iron loading with age. The serum ferritin and serum alanine transaminase levels were significantly raised in the patients who were given blood transfusions. In the presence of blood transfusions, and absence of adequate iron chelation therapy, splenectomy became an inevitable event at some stage of the disease because of increasing transfusing requirements.
83 Malays with HbE beta-thalassaemia who were not transfusion dependent were investigated. 79 persons showed no beta0 formation indicating the predominant gene in Malays with HbE beta-thalassaemia was beta0. HbF assays showed levels that were similar to transfusion dependent patients. Further studies are necessary to determine the presence of the alpha, (alpha+) gene Interacting with HbE and beta0 to produce the milder phenotype of HbE beta-thalassaemla.
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).
Introduction: Filipino β°-deletion is predominant among the β-thalassaemia patients in the indigenous population of Sabah, Malaysia particularly among the Kadazandusun. Individuals who co-inherit with α- and β-thalassaemia will demonstrate milder clinical symptoms with modified complete blood count (CBC) and Hb subtype parameters. HBS1L-MYB variants act as one of the key regulator of haematopoiesis and erythropoiesis and display strong association
with variation of HbF levels. Therefore, this study aims to evaluate the association between genetic variants in HBS1L-MYB with Hb subtypes level among Filipino β°-deletion carriers co-inherited with -α3.7 deletion. Methods: Filipino β°-deletion and -α3.7 deletion were identified using gap-polymerase chain reaction (PCR). A total of 34 subjects found with coinheritance of Filipino β°-deletion and -α3.7 deletion were subjected for HBS1L-MYB intergenic polymorphisms (HMIP) analysis. Hb subtypes level were quantified using BioRad Variant II Hb analyser. Genotyping of HBS1L-MYB variants rs9399137 and rs11759553 was done using own designed tetra primer ARMS-PCR. Results: The minor allele frequencies (MAF) of the two HMIP is found more than 0.05 (rs11759553, MAF=0.18 and rs9399137, MAF=0.15), indicating the significance of these variants among the study subjects. Significant difference was found between HbF level and HBS1L-MYB variant rs11759553 with p-value less than 0.05 (p=0.001). Subjects with homozygous genotype for rs11759553 (T/T) was found with higher HbF, followed by heterozygous (A/T) and wild type (A/A). rs11759553 and rs9399137 was found did not influence the level of HbA and HbA2. HMIP of rs11759553 and rs9399137 are found significant among Filipino β°-deletion carriers co-inherited with -α3.7deletion with its high minor allelic frequency and high HbF level. Strong association with HbF level was demonstrated when
coinheritance of rs11759553. Conclusion: This study demonstrates that there are significant associations between certain genetic variants in HBS1L-MYB with Hb subtypes level among Filipino β°-deletion carriers co-inherited with -α3.7 deletion.