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Supawadee Yamsri

Bio: Supawadee Yamsri is an academic researcher from Khon Kaen University. The author has contributed to research in topics: Thalassemia & Prenatal diagnosis. The author has an hindex of 12, co-authored 30 publications receiving 413 citations.

Papers
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Journal ArticleDOI
TL;DR: To demonstrate the performance of thalassemia prevention in northeast Thailand during 1993–2008, a large number of patients diagnosed with the disease during this period had to be referred to a hospital for treatment.
Abstract: Objective To demonstrate the performance of thalassemia prevention in northeast Thailand during 1993-2008. Methods Retrospective data from 1422 at-risk couples who attended from January 1993 to December 2008 were studied. All couples were suspected at-risk couples based on initial screening using standard protocols. Three thalassemia carrier types including alpha(0)-thalassemia, beta-thalassemia and hemoglobin E were identified using standard methods. Data on prenatal diagnosis were collected. Results Of the 1422 positive-screened couples, 1254 (88.2%) were diagnosed as true-positive couples. After DNA analysis, 968 of 1254 (77.2%) resulted at risk for three types of severe conditions being hemoglobin E-beta-thalassemia disease (640/968, 66.1%), homozygous alpha(0)-thalassemia (304/968, 31.4%) and homozygous beta-thalassemia (11/968, 1.1%). The remaining 1.3% of the couples were at risk for more than one disease. After genetic counseling, prenatal diagnosis was performed on 756 couples (78.1%). The proportions of affected fetuses, thalassemia carriers and unaffected fetuses were 26.9, 50.0 and 23.0%, respectively. Conclusion Implementation of a prevention and control program accompanying with a referral system for prenatal diagnosis is technically feasible in northeast Thailand and a large number of severe thalassemia diseases have been prevented during the past 16 years of operation.

100 citations

Journal ArticleDOI
TL;DR: The findings underline the heterogeneity of β-thalassemia and the importance of hematological and molecular analyses of both α-and β -thalassemias in the diagnosis and genetic counseling of the couples at-risk of having babies with severe thalassemia diseases in the region.
Abstract: In order to update the molecular basis of β-thalassemia and describe hematological features among different mutations and the concurrent of α- and β-thalassemias, 849 unrelated β-thalassemia heterozygotes recruited in northeast Thailand during a prevention and control program were studied. β- and α-thalassemia mutations were investigated using the polymerase chain reaction (PCR)-based technologies and hematological parameters were recorded using standard methods. Seventeen different mutations including both β(0)- and β(+) -thalassemias were identified. Eight of these 17 β-thalassemia alleles accounted for 97.4%, others were found at lower frequencies (<1.0%). Of the 849 cases, 626 were investigated for common α-thalassemia mutations and 155 (24.8%) were found to be co-inherited with different forms of α-thalassemia. Comparison of the hematological parameters among different β-thalassemia mutations revealed an increasing trend of MCV and MCH in a group of heterozygous states for the 3.4kb deletion and the A-G substitution at nucleotide (NT) -28. Hb A(2) and Hb F levels in individuals with the 3.4kb deletion were significantly higher than those with other mutations. Interaction of each β-thalassemia mutation with α-thalassemia did not affect the diagnostic ranges of Hb A(2) and Hb F, though the significantly increased MCV and MCH was noted. These findings underline the heterogeneity of β-thalassemia and the importance of hematological and molecular analyses of both α-and β-thalassemias in the diagnosis and genetic counseling of the couples at-risk of having babies with severe thalassemia diseases in the region.

68 citations

Journal ArticleDOI
TL;DR: Different phenotypic expression of Hb A(2), H b E and Hb F could help in differential diagnosis of these Hb E related disorders commonly encountered in the regions where access to molecular techniques is limited.
Abstract: Study on the phenotypic expression of hemoglobin (Hb) A(2) and Hb E in Hb E disorders has been difficult due to the co-separation of Hb A(2) and Hb E in most Hb analysis assays. Because these two Hbs are separated on capillary electrophoresis, we studied phenotypic expression of Hbs A(2), E and F in various Hb E disorders using this system. This was done on 362 subjects with several Hb E disorders including heterozygous Hb E, homozygous Hb E, β-thalassemia/Hb E, δβ-thalassemia/Hb E, and Hb Lepore/Hb E and those of these disorders with several forms of α-thalassemia. Normal controls showed Hb A(2) of 2.7 ± 0.3%. Heterozygous Hb E and homozygous Hb E had elevated Hb A(2) i.e. 3.8 ± 0.3% and 4.8 ± 0.5%, respectively. Further elevations were observed for β(0)-thalassemia/Hb E (6.1 ± 1.9%) and β(+)-thalassemia/Hb E (7.1 ± 1.2%). Interestingly, no elevation of Hb A(2) was found in the δβ-thalassemia/Hb E, and Hb Lepore/Hb E (2.3 ± 0.3%) but higher Hb F levels were noted which could be useful diagnostic markers. The levels of Hb E were variable. Co-inheritance of these Hb E disorders with α-thalassemia were associated with lower outputs of Hb E and Hb F but the levels of Hb A(2) were not altered. Different phenotypic expression of Hb A(2), Hb E and Hb F could help in differential diagnosis of these Hb E related disorders commonly encountered in the regions where access to molecular techniques is limited.

43 citations

Journal ArticleDOI
TL;DR: A pyrophosphorolysis‐activated polymerization assay for non‐invasive prenatal diagnosis (NIPD) of β‐thalassemia major and sickle‐cell disease is developed.
Abstract: Objective The aim of this study was to develop a pyrophosphorolysis-activated polymerization (PAP) assay for non-invasive prenatal diagnosis (NIPD) of β-thalassemia major and sickle-cell disease (SCD). PAP is able to detect mutations in free fetal DNA in a highly contaminating environment of maternal plasma DNA. Methods Pyrophosphorolysis-activated polymerization primers were designed for 12 informative SNPs, genotyped by melting curve analysis (MCA) in both parents. The PAP assay was tested in a series of 13 plasma DNA samples collected from pregnant women. A retrospective NIPD was performed in a couple at risk for SCD. Results All PAP reactions were optimized and able to detect 97% wildtype gDNA. In all 13 cases, the paternal allele was detected by PAP in maternal plasma at 10 to 18 weeks of gestation. For the couple at risk, PAP showed presence of the normal paternal SNP allele in maternal plasma, which was confirmed by results of the chorionic villus sampling analysis. Conclusions In contrast to other methods used for NIPD, the combined PAP and MCA analysis detecting the normal paternal allele is also applicable for couples at risk carrying the same mutation, provided that a previously born child is available for testing to determine the linkage to the paternal SNPs. © 2012 John Wiley & Sons, Ltd.

42 citations

Journal ArticleDOI
TL;DR: Overlapping levels of Hb E, Hb F, and other hematological parameters were observed which did not predict clinical severity, indicating a need for α-globin gene analysis for accurate diagnosis and improved genetic counseling.
Abstract: We describe hematologic and DNA characterization of hemoglobin (Hb) E homozygote with various forms of α-thalassemia in Thai individuals. Altogether, 131 unrelated adult subjects with Hb EE at routine Hb analysis were studied. Forty-two cases were found to carry α-thalassemia with ten different genotypes. These included 21 cases with α+-thalassemia heterozygote (–α3.7/αα), one case with α+-thalassemia heterozygote (–α4.2/αα), six cases with Hb Constant Spring heterozygote (αCSα/αα), four cases with homozygous α+-thalassemia (–α3.7/–α3.7), one case with homozygous α+-thalassemia (–α4.2/–α4.2), two cases with compound α+-thalassemia/Hb Constant Spring (–α3.7/αCSα), one case with compound α+-thalassemia/Hb Pakse (–α3.7/αPSα), four cases with α0-thalassemia heterozygote (––SEA/αα), and, unexpectedly, two cases with compound α0-thalassemia/α+-thalassemia [(––SEA/–α3.7) and (––SEA/–α4.2)]. The hematological expression of these Hb E homozygotes with various forms of α-thalassemia was presented comparatively with those of the 89 cases of pure Hb E homozygotes. Overlapping levels of Hb E, Hb F, and other hematological parameters were observed which did not predict clinical severity, indicating a need for α-globin gene analysis for accurate diagnosis and improved genetic counseling.

36 citations


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TL;DR: The range of methods currently available in a clinical setting as well as emerging approaches in clinical molecular diagnostics are reviewed, and implementation challenges that will be necessary to address to ensure the future of genetic medicine are outlined.
Abstract: The authors review current technologies for clinical genetic testing. Moves are being made towards whole-genome and whole-exome sequencing in the clinic, although other technologies will continue to be of value. Genomic technologies are reaching the point of being able to detect genetic variation in patients at high accuracy and reduced cost, offering the promise of fundamentally altering medicine. Still, although scientists and policy advisers grapple with how to interpret and how to handle the onslaught and ambiguity of genome-wide data, established and well-validated molecular technologies continue to have an important role, especially in regions of the world that have more limited access to next-generation sequencing capabilities. Here we review the range of methods currently available in a clinical setting as well as emerging approaches in clinical molecular diagnostics. In parallel, we outline implementation challenges that will be necessary to address to ensure the future of genetic medicine.

343 citations

Journal Article
TL;DR: In this paper, the inherited hemoglobin disorders pose an increasing burden on global health resources in the future, due to natural selection combined with a high frequency of consanguineous marriages in many countries, together with an epidemiological transition.
Abstract: Although information about the precise world distribution and frequency of the inherited hemoglobin disorders is still limited, there is no doubt that they are going to pose an increasing burden on global health resources in the future. Their high frequency is a reflection of natural selection combined with a high frequency of consanguineous marriages in many countries, together with an epidemiological transition; whereby, as public health measures improve in the poorer countries of the world, more babies with these disorders are surviving to present for treatment.

196 citations

Journal ArticleDOI
TL;DR: There exists a significant need for non‐invasive prenatal diagnosis of single‐gene disorders, and the continuing advances in technology and data analysis should facilitate the expansion of the NIPD test repertoire.
Abstract: Recently, we have witnessed the rapid translation into clinical practice of non-invasive prenatal testing for the common aneuploidies, most notably within the United States and China. This represents a lucrative market with testing being driven by companies developing and offering their services. These tests are currently aimed at women with high/medium-risk pregnancies identified by serum screening and/or ultrasound scanning. Uptake has been impressive, albeit limited to the commercial sector. However, non-invasive prenatal diagnosis (NIPD) for single-gene disorders has attracted less interest, no doubt because this represents a much smaller market opportunity and in the majority of cases has to be provided on a bespoke, patient or disease-specific basis. The methods and workflows are labour-intensive and not readily scalable. Nonetheless, there exists a significant need for NIPD of single-gene disorders, and the continuing advances in technology and data analysis should facilitate the expansion of the NIPD test repertoire. Here, we review the progress that has been made to date, the different methods and platform technologies, the technical challenges, and assess how new developments may be applied to extend testing to a wider range of genetic disorders. © 2013 John Wiley & Sons, Ltd.

133 citations

Journal ArticleDOI
14 Apr 2016-Blood
TL;DR: A broad range of hitherto unrelated human red cell disorders are caused by variants in KLF1, a master regulator of erythropoiesis, which were previously considered to be extremely rare causes of human genetic disease.

124 citations

Journal ArticleDOI
TL;DR: This classification has embraced all other forms of thalassemia syndromes such as α-thalassemia, hemoglobin E/β-thalassesmia and combined α- and β-thalasemias.
Abstract: At present, thalassemia diseases are classified into transfusion-dependent thalassemia and non-transfusion-dependent thalassemia. This classification is based on the clinical severity of patients determining whether they do require regular blood transfusions to survive (transfusion-dependent thalassemia) or not (non-transfusion-dependent thalassemia). In addition to the previous terminology of "thalassemia major" or "thalassemia intermedia," this classification has embraced all other forms of thalassemia syndromes such as α-thalassemia, hemoglobin E/β-thalassemia and combined α- and β-thalassemias. Definitive diagnosis of thalassemia and hemoglobinopathies requires a comprehensive workup from complete blood count, hemoglobin analysis, and molecular studies to identify mutations of globin genes.

101 citations