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1.
Hemoglobin ; 42(4): 247-251, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30623696

RESUMO

Nondeletional α-globin mutations are known to cause more serious clinical effects than deletional ones. A rare IVS-I-1 (G>A) (HBA2: c.95+1G>A) donor splice site mutation interferes with normal splicing of pre mRNA and results in activation of a cryptic splice site as well as a frameshift mutation. Hb Adana [HBA2: c.179G>A (or HBA1)] is a highly unstable variant hemoglobin (Hb) resulting from a mutation at codon 59 on the HBA2 or HBA1 gene, recognized to cause severe α-thalassemia (α-thal) syndromes. We report a unique case of compound heterozygosity for these two mutations in a 9-year-old boy who presented with a Hb level of 5.3 g/dL and hepatomegaly at the age of 15 months. He required regular blood transfusions in view of a Hb level of <7.0 g/dL and failure to thrive. He had thalassemic red cell indices and peripheral blood film. The Hb electrophoresis only showed a raised Hb F level (3.3%) and a pre run peak but the Hb H inclusion test was negative. His father had thalassemic red cell indices but a normal Hb level. His mother had almost normal Hb levels and red cell indices. Hb Adana involving the HBA2 gene was detected by mutiplex amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) in the proband and his father. DNA sequencing of the HBA2 gene confirmed the IVS-I-1 mutation in the proband and his mother. This case highlighted the unique interaction of the IVS-I-1 mutation with Hb Adana in a young Malay boy presenting with transfusion-dependent α-thal.


Assuntos
Hemoglobina A2/genética , Hemoglobinas Anormais/genética , Talassemia alfa/genética , Criança , Diagnóstico Diferencial , Índices de Eritrócitos , Heterozigoto , Humanos , Masculino , Sítios de Splice de RNA , alfa-Globinas/genética
2.
Ann Hum Genet ; 81(5): 205-212, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28620953

RESUMO

Thalassaemia is a public health problem in Malaysia, with each ethnic group having their own common mutations. However, there is a lack on data on the prevalence and common mutations among the indigenous people. This cross-sectional study was performed to determine the common mutations of α- and ß-thalassaemia among the subethnic groups of Senoi, the largest Orang Asli group in Peninsular Malaysia. Blood samples collected from six Senoi subethnic groups were analysed for full blood count and haemoglobin analysis (HbAn). Samples with abnormal findings were then screened for α- and ß-globin gene mutations. Out of the 752 samples collected, 255 showed abnormal HbAn results, and 122 cases showing abnormal red cell indices with normal HbAn findings were subjected to molecular screening. DNA analysis revealed a mixture of α- and ß-globin gene mutations with 25 concomitant cases. The types of gene abnormalities detected for α-thalassaemia were termination codon (T>C) Hb CS (αCS α), Cd59 (G>A) haemoglobin Adana (Hb Adana) (αCd59 α), initiation codon (ATG>A-G) (αIniCd α), two-gene deletion (-SEA ), and single-gene 3.7-kb deletion (-α3.7 ). For ß-thalassaemia, there were Cd26 (G>A) Hb E (ßE ), Cd19 (A>G) Haemoglobin Malay (Hb Malay) (ßCd19 ), and IVS 1-5 (G>C) (ßIVS 1-5 ).


Assuntos
alfa-Globinas/genética , Talassemia alfa/genética , Globinas beta/genética , Talassemia beta/genética , Povo Asiático/genética , Estudos Transversais , Análise Mutacional de DNA , Estudos de Associação Genética , Humanos , Malásia , Talassemia alfa/epidemiologia , Talassemia beta/epidemiologia
3.
Hum Genet ; 133(9): 1169-85, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24916469

RESUMO

Peninsular Malaysia is a strategic region which might have played an important role in the initial peopling and subsequent human migrations in Asia. However, the genetic diversity and history of human populations--especially indigenous populations--inhabiting this area remain poorly understood. Here, we conducted a genome-wide study using over 900,000 single nucleotide polymorphisms (SNPs) in four major Malaysian ethnic groups (MEGs; Malay, Proto-Malay, Senoi and Negrito), and made comparisons of 17 world-wide populations. Our data revealed that Peninsular Malaysia has greater genetic diversity corresponding to its role as a contact zone of both early and recent human migrations in Asia. However, each single Orang Asli (indigenous) group was less diverse with a smaller effective population size (N(e)) than a European or an East Asian population, indicating a substantial isolation of some duration for these groups. All four MEGs were genetically more similar to Asian populations than to other continental groups, and the divergence time between MEGs and East Asian populations (12,000--6,000 years ago) was also much shorter than that between East Asians and Europeans. Thus, Malaysian Orang Asli groups, despite their significantly different features, may share a common origin with the other Asian groups. Nevertheless, we identified traces of recent gene flow from non-Asians to MEGs. Finally, natural selection signatures were detected in a batch of genes associated with immune response, human height, skin pigmentation, hair and facial morphology and blood pressure in MEGs. Notable examples include SYN3 which is associated with human height in all Orang Asli groups, a height-related gene (PNPT1) and two blood pressure-related genes (CDH13 and PAX5) in Negritos. We conclude that a long isolation period, subsequent gene flow and local adaptations have jointly shaped the genetic architectures of MEGs, and this study provides insight into the peopling and human migration history in Southeast Asia.


Assuntos
Povo Asiático/genética , Variação Genética , Grupos Populacionais/genética , Adaptação Fisiológica , Povo Asiático/etnologia , Evolução Molecular , Estruturas Genéticas , Genética Populacional , Estudo de Associação Genômica Ampla , Genótipo , Haplótipos , Heterozigoto , Humanos , Malásia/etnologia , Polimorfismo de Nucleotídeo Único , Grupos Populacionais/etnologia , Fatores de Tempo
4.
J Hum Genet ; 58(4): 189-94, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23389243

RESUMO

The combination of two silent mutations, c.1311C>T in exon 11 and IVS11 T93C (glucose-6-phosphate dehydrogenase (G6PD) 1311T/93C), with unknown mechanism, have been reported in G6PD-deficient individuals in Asian populations including Malaysian aboriginal group, Negrito. Here, we report the screening of G6PD gene in 103 Negrito volunteers using denaturing high-performance liquid chromatography (dHPLC) and direct sequencing. A total of 48 individuals (46.6%) were G6PD deficient, 83.3% of these carried G6PD 1311T/93C with enzyme activity ranging from 1.8 to 4.8 U gHb(-1). Three novel single-nucleotide polymorphisms (SNPs), rs112950723, rs111485003 and rs1050757, were found in the G6PD 3'-untranslated region (UTR). Strong association was observed between haplotype 1311T/93C and rs1050757G, which is located inside the 35 bp AG-rich region. In silico analysis revealed that the transition of A to G at position rs1050757 makes significant changes in the G6PD mRNA secondary structure. Moreover, putative micro (mi)RNA target sites were identified in 3'-UTR of G6PD gene, two of these in the region encompassing rs1050757. It could be speculated that rs1050757 have a potential functional effect on the downregulation of mRNA and consequently G6PD deficiency either by affecting mRNA stability and translation or mirRNA regulation process. This is the first report of biochemical association of an SNP in 3'-UTR of G6PD gene and the possible role of mRNA secondary structure.


Assuntos
Regiões 3' não Traduzidas , Variação Genética , Deficiência de Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/genética , Povo Asiático , Sequência de Bases , Feminino , Genótipo , Humanos , Masculino , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Polimorfismo de Nucleotídeo Único
5.
Front Genet ; 14: 1098828, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37388931

RESUMO

Background: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked hereditary disorder and a global public health concern that is most prevalent in malaria-endemic regions including Asia, Africa, and the Mediterranean. G6PD-deficient individuals are at high risk of developing acute hemolytic anemia following treatment with antimalarial drugs including Primaquine and Tafenoquine. However, the currently available tests for G6PD screening are complex and often have been misclassifying cases, particularly for females with intermediate G6PD activity. The latest innovation of quantitative point-of-care (POC) tests for G6PD deficiency provides an opportunity to improve population screening and prevent hemolytic disorders when treating malaria. Aim(s): To assess the evidence on the type and performance of quantitative point-of-care (POC) tests for effective G6PD screening and hence, radical elimination of Plasmodium malaria infections. Methods: Relevant studies published in English language confined from two databases, Scopus and ScienceDirect were searched from November 2016 onwards. The search was conducted using keywords including "glucosephosphate dehydrogenase" or "G6PD", "point-of-care", "screening" or "prevalence", "biosensor" and "quantitative". The review was reported following the PRISMA guidelines. Results: Initial search results yielded 120 publications. After thorough screening and examination, a total of 7 studies met the inclusion criteria, and data were extracted in this review. Two types of quantitative POC tests were evaluated, namely, the CareStartTM Biosensor kit and the STANDARD G6PD kit. Both tests showed promising performance with high sensitivity and specificity ranging mostly from 72% to 100% and 92%-100%, respectively. The positive and negative predictive values (PPV and NPV) ranged from 35% to 72% and 89%-100%, with accuracy ranging from 86% to 98%. Conclusion: In areas with a high prevalence of G6PD deficiency that overlap with malaria endemicity, availability and validation of the diagnostic performance of quantitative POC tests are of absolute importance. Carestart™ biosensor and STANDARD G6PD kits showed high reliability and performed well in comparison to the spectrophotometric reference standard.

6.
PLoS One ; 18(12): e0294891, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38085718

RESUMO

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an X-linked genetic disorder characterized by reduced G6PD enzyme levels in the blood. This condition is common in populations exposed to malaria; an acute febrile disease caused by Plasmodium parasites. G6PD-deficient individuals may suffer from acute hemolysis following the prescription of Primaquine, an antimalarial treatment. The population at risk for such a condition includes the Senoi group of Orang Asli, a remote indigenous community in Malaysia. This study aimed to elucidate the G6PD molecular heterogeneity in this subethnic group which is important for malaria elimination. A total of 662 blood samples (369 males and 293 females) from the Senoi subethnic group were screened for G6PD deficiency using a quantitative G6PD assay, OSMMR2000-D kit with Hb normalization. After excluding the family members, the overall prevalence of G6PD deficiency in the studied population was 15.2% (95% CI: 11-19%; 56 of 369), with males (30 of 172; 17.4%) outnumbering females (26 of 197; 13.2%). The adjusted male median (AMM), defined as 100% G6PD activity, was 11.8 IU/gHb. A total of 36 participants (9.6%; 26 male and 10 female) were deficient (<30% of AMM) and 20 participants (5.4%; 4 male and 16 female) were G6PD-intermediate (30-70% of AMM). A total of 87 samples were genotyped, of which 18 showed no mutation. Seven mutations were found among 69 genotyped samples; IVS11 T93C (47.1%; n = 41), rs1050757 (3'UTR +357A>G)(39.1%; n = 34), G6PD Viangchan (c.871G>A)(25.3%; n = 22), G6PD Union (c.1360C>T)(21.8%; n = 19), c.1311C>T(20.7%; n = 18), G6PD Kaiping (c.1388G>A)(8.0%; n = 7), and G6PD Coimbra (c.592C>T)(2.3%; n = 2). Our analysis revealed 27 hemizygote males, 18 heterozygote females, 7 homozygote females, and 2 compound heterozygote females. This study confirms the high prevalence of G6PD deficiency among the Senoi Malaysian Orang Asli, with a significant degree of molecular heterogeneity. More emphasis should be placed on screening for G6PD status and proper and safe use of Primaquine in the elimination of malaria among this indigenous population.


Assuntos
Deficiência de Glucosefosfato Desidrogenase , Malária , Feminino , Humanos , Masculino , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/análise , Deficiência de Glucosefosfato Desidrogenase/epidemiologia , Deficiência de Glucosefosfato Desidrogenase/genética , Deficiência de Glucosefosfato Desidrogenase/diagnóstico , Malária/epidemiologia , Malásia/epidemiologia , Prevalência , Primaquina/efeitos adversos
7.
PLoS One ; 11(4): e0153752, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27105431

RESUMO

OBJECTIVE: Interleukin-1 receptor antagonist (IL-1Ra) acts as an inhibitor of IL-1; which is one of the culprit cytokines in rheumatoid arthritis (RA). Although +2018 polymorphism of IL-1Ra has been implicated in the pathogenesis of RA, its importance remains poorly understood. Hence, the purpose of this study was to determine the clinical significance of interleukin-1 receptor antagonist (IL-1Ra) +2018 polymorphism in RA. METHODS: Polymerase chain reaction (PCR) and sequencing were used to determine the genotypes of the IL-1Ra +2018 for 77 RA patients and 18 healthy controls. All RA patients were assessed for the disease activity score that includes 28 joints (DAS28) and radiographic disease damage based on Modified Sharp Score (MSS). RESULTS: The frequency of the T/T and C/T genotypes did not differ significantly (p = 0.893) between the RA patients and the controls. The C/T genotype had significantly higher mean disease activity (DAS 28) and disease damage (MSS) scores with p values of 0.017 and 0.004, respectively. Additionally, the ESR (erythrocyte sedimentation rate), CRP (C-reactive protein), the number of swollen and tender joints were higher for the C/T individuals. On multivariate analysis the CRP, swollen joint count and MSS remained significant with the following p values i.e. 0.045, 0.046 and less than 0.05. CONCLUSIONS: C/T genotype of IL-1Ra +2018 prognosticates more aggressive disease in RA.


Assuntos
Artrite Reumatoide/genética , Proteína Antagonista do Receptor de Interleucina 1/genética , Polimorfismo Genético , Adulto , Idoso , Estudos de Casos e Controles , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
8.
BMC Res Notes ; 8: 176, 2015 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-25925844

RESUMO

BACKGROUND: The Malaysian Node of the Human Variome Project (MyHVP) is one of the eighteen official Human Variome Project (HVP) country-specific nodes. Since its inception in 9(th) October 2010, MyHVP has attracted the significant number of Malaysian clinicians and researchers to participate and contribute their data to this project. MyHVP also act as the center of coordination for genotypic and phenotypic variation studies of the Malaysian population. A specialized database was developed to store and manage the data based on genetic variations which also associated with health and disease of Malaysian ethnic groups. This ethnic-specific database is called the Malaysian Node of the Human Variome Project database (MyHVPDb). FINDINGS: Currently, MyHVPDb provides only information about the genetic variations and mutations found in the Malays. In the near future, it will expand for the other Malaysian ethnics as well. The data sets are specified based on diseases or genetic mutation types which have three main subcategories: Single Nucleotide Polymorphism (SNP), Copy Number Variation (CNV) followed by the mutations which code for the common diseases among Malaysians. MyHVPDb has been open to the local researchers, academicians and students through the registration at the portal of MyHVP ( http://hvpmalaysia.kk.usm.my/mhgvc/index.php?id=register ). CONCLUSIONS: This database would be useful for clinicians and researchers who are interested in doing a study on genomics population and genetic diseases in order to obtain up-to-date and accurate information regarding the population-specific variations and also useful for those in countries with similar ethnic background.


Assuntos
Bases de Dados Genéticas , Etnicidade/genética , Humanos , Malásia
9.
Am J Blood Res ; 4(1): 33-40, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25232503

RESUMO

The aim of this study was to adapt MARMS with some modifications to detect beta mutation in our cohort of thalassemia patients. We focused only on transfusion-dependent thalassemia Malay patients, the predominant ethnic group (95%) in the Kelantanese population. Eight mutations were identified in 46 out of 48 (95.83%) beta thalassemia alleles. Most of the patients (54.2%) were compound heterozygous with co-inheritance Cd 26 (G>A). The frequencies of spectrum beta chain mutation among these patients are presented in Table 2. Among the transfusion dependent beta thalassemia Malay patients studied, 26 patients were found to be compound heterozygous and the main alleles were Cd 26 (G>A). Compound heterozygous mutation of Cd 26 (G>A) and IVS 1-5 (G>C) were 12 (46.2%), Cd 26 (G>A) and Cd 41/42 (TTCT) were 9 (34.6%), Cd 26 (G>A) and IVS 1-1 (G>C) were 2 (7.7%) respectively. Meanwhile the minority were made of a single compound heterozygous of Cd 26 (G>A) and Cd 71/72, Cd 26 (>A) and Cd 17 (A>T), Cd 26 (G>A) and -28 (G>A) respectively. Twenty out of forty six patients were shown to have homozygous of IVS 1-5 (G>C) were 2 (10.0%), Cd 26 (G>A) were 15 (75.0%), Cd 19 (A>G) were 1 (5.0%), and IVS 1-1 (G>T) were 2 (10.0%). The beta chain mutations among the Kelantanese Malays followed closely the distribution of beta chain mutations among the Thais and the Malays of the Southern Thailand. The G-C transition at position 5 of the IVS 1-5 mutation was predominant among the Malay patients. In conclusion, this method has successfully identified the mutation spectrum in our cohort of transfusion-dependent beta thalassemia patients, and this method is equally effective in screening for mutation among thalassemia patients.

10.
Cancer Lett ; 311(1): 77-84, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21824723

RESUMO

Carbonyl reductase (CR) is an NADPH-dependent, mostly monomeric, cytosolic enzyme with broad substrate specificity for carbonyl compounds. CR appears to be involved in the regulation of tumour progression. However, molecular mechanisms of CR in tumour progression and clinical significance of CR status remain unclear in human uterine squamous cell carcinoma (SCC). Here, we investigated the clinical significance of CR using immunohistochemical analyses of human uterine cervical SCC tissues and how CR affects cancer cell behaviour in vitro. Paraffin sections from uterine cervical SCC tissues, FIGO stage Ib1-IIb (n = 67) were immunostained with anti-CR antibodies. Overall survival (OS) and progression-free survival (PFS) were analyzed by the Kaplan-Meier method. Sense and antisense CR cDNAs were transfected into a human uterine SCC cell line (SiHa) to investigate the role of CR in cancer cell invasion and metastasis. Immunohistochemical analyses showed that reduced CR expression patterns in primary cancer lesions were closely associated with a high incidence of pelvic lymph node metastasis, poor OS, and poor PFS. In an in vitro experiment, suppression of CR increased cancer cell invasion, secretion of MMP-2, -9 and cyclooxygenase-2 (COX-2) expression and decreased E-cadherin expression. On the other hand, over-expression of CR increased E-cadherin expression and decreased MMP-2, -9 secretion and COX-2 expression. The reduced CR expression pattern, as measured by immunohistochemistry, can be a useful predictor of lymph node metastasis and poor prognosis in patients with uterine SCC. This clinical result is supported by the in vitro data which show that suppression of CR expression promotes cancer cell invasion with decreased E-cadherin expression and increased MMP-2, -9 secretion.


Assuntos
Oxirredutases do Álcool/antagonistas & inibidores , Carcinoma de Células Escamosas/enzimologia , Neoplasias do Colo do Útero/enzimologia , Oxirredutases do Álcool/biossíntese , Oxirredutases do Álcool/metabolismo , Caderinas/biossíntese , Caderinas/genética , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Ciclo-Oxigenase 2/biossíntese , Ciclo-Oxigenase 2/genética , Inibidores de Ciclo-Oxigenase 2/farmacologia , DNA Antissenso/administração & dosagem , DNA Antissenso/genética , Intervalo Livre de Doença , Precursores Enzimáticos/biossíntese , Precursores Enzimáticos/genética , Feminino , Gelatinases/biossíntese , Gelatinases/genética , Humanos , Imuno-Histoquímica , Metástase Linfática , Metaloproteinase 2 da Matriz/biossíntese , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/biossíntese , Metaloproteinase 9 da Matriz/genética , Invasividade Neoplásica , Prognóstico , Transfecção , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
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