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To describe rare genetic interactions of α-thalassemia alleles causing Hb H disease and Hb Bart’s hydrops fetalis which could lead to diagnostic errors in a routine practice.Hematological and molecular characterization were carried out in a Thai family with a risk of having fetus with Hb Bart’s hydrops fetalis.Both parents were found to be the thalassemia intermedia patients associated with unusual forms of Hb H disease. DNA analysis of common α-thalassemia mutations in Thailand identified α+-thalassemia (-α3.7 kb del) and unknown α0-thalassemia in the father and α0-thalassemia (--SEA) with unknown α+-thalassemia in the mother. Fetal DNA analysis unlikely identified a homozygosity for α0-thalassemia (--SEA/--SEA). Further analysis identified that the father carried a rare South African α0-thalassemia in combination with α+-thalassemia (--SA/-α), whereas the mother was a patient with Hb H-Queens Park disease (--SEA/ααQP). The fetus was, in fact, a compound heterozygote for (--SA/--SEA).As shown in this study, routine screening for α-thalassemia at prenatal diagnosis in the region should include both common and rare α0-thalassemia alleles found in the population to effectively prevent a fatal condition of Hb Bart’s hydrops fetalis syndrome. [ABSTRACT FROM AUTHOR]

Objective: To determine the frequency and etiology of unnecessary prenatal diagnosis for hemoglobinopathies during 12 years of services at a single university center in Thailand. Methods: We conducted a retrospective cohort analysis of prenatal diagnosis during 2009–2021. A total of 4,932 couples at risk and 4,946 fetal specimens, including fetal blood (5.6%), amniotic fluid (92.3%), and chorionic villus samples (2.2%) were analyzed. Identification of mutations causing hemoglobinopathies was carried out by PCR-based methods. Maternal contamination was monitored by analysis of the D1S80 VNTR locus. Results: Among 4,946 fetal specimens, 12 were excluded because of poor PCR amplification, maternal contamination, non-paternity, and inconsistency of the results of the fetuses and parents. Breakdown of 4,934 fetuses revealed 3,880 (78.6%) at risk for the three severe thalassemia diseases, including β-thalassemia major, Hb E-β-thalassemia, and homozygous α0-thalassemia, 58 (1.2%) at risk for other α-thalassemia diseases, 168 (3.4%) at risk for β+-thalassemia, 109 (2.2%) at risk for high Hb F determinants, 16 (0.3%) at risk for abnormal Hbs, and 294 (6.0%) with no risk of having severe hemoglobinopathies. The parents of 409 (8.3%) fetuses had inadequate data for fetal risk assessment. Overall, we encountered unnecessary prenatal diagnostic requests for 645 (13.1%) fetuses. Conclusions: The frequency of unnecessary prenatal diagnosis was high. This could lead to unnecessary risk of complications associated with fetal specimen collection, psychological impacts to the pregnant women and their families, as well as laboratory expenses and workload. [ABSTRACT FROM AUTHOR]

Introduction: Hemoglobinopathies are major public health problems worldwide. Accurate laboratory diagnosis of the carrier is essential, which includes initial screening, Hb analysis, and DNA analysis. For the first time, we have developed a single‐tube quality control (QC) sample for these laboratory tests. Methods: The QC sample was made from a lyophilized mixture of the stabilized hemolysate with carbon monoxide saturation and the white blood cells of known thalassemia mutations. Homogeneity and stability were examined by Hb and DNA analyses on day 0 and every month for 12 months, at room temperature, 4°C, and −20°C. A preliminary proficiency testing (PT) program for hemoglobinopathies using this single QC material was developed. Results: Hemoglobin (Hb) and DNA analyses of a single‐tube QC sample demonstrated satisfactory results of Hb analysis for at least five months and DNA analysis for at least one year of storage at −20°C. The results obtained from a preliminary PT program on five expert laboratories confirmed that a single tube QC sample prepared could be used as a PT item with various Hb and DNA analyses methods. Conclusion: A single lyophilized control sample has been generated for use in hemoglobinopathies' internal and external quality control program. Unlike other available control materials, which are used for individual testing, a single‐tube QC sample generated can be used to control the pre‐analytical and analytical processes of both Hb and DNA analyses and is suitable for use in the PT program of hemoglobinopathies. [ABSTRACT FROM AUTHOR]

Hemoglobin Constant Spring (Hb CS) and Hb Pakse' (PS) are the common non-deletional α+-thalassemia found in Thailand. These two variants can cause severe thalassemia syndromes, especially in fetus and neonate. Molecular diagnosis is the only confirmatory method because Hb CS and Hb PS are usually missed by routine screening and Hb analysis. Therefore, we aimed to develop rapid direct PCR for the diagnosis of Hb CS and PS genes. Multiplex direct PCR assays for identifying the Hb CS and PS genes in whole blood (WB) and amniotic fluid (AF) specimens were developed. The assays were firstly validated on 290 unrelated whole blood specimens. Hb CS and PS carriers were identified in 67 (23.1%) and 6 (2.1%) cases, respectively. A 100% concordant result as compared to routine PCR assay was observed. The direct PCR assays have been applied successfully for prenatal diagnosis in two families. The result showed that the fetuses were affected by homozygous Hb CS and compound heterozygous Hb CS/Hb PS. Accurate prenatal diagnosis of these families was observed using the newly developed assays. These assays should be applicable in routine thalassemia diagnostics as well as in the large-scale screening of Hb CS and PS in the region. [ABSTRACT FROM AUTHOR]

Objective Prenatal and postnatal diagnosis of hemoglobin E-β 0-thalassemia can be made using polymerase chain reaction (PCR) analysis mostly on purified DNA. We have establihed a direct amplification method without DNA extraction on whole blood (WB) and amniotic fluid (AF) specimens to diagnose the disease. Methods Three reactions of WB PCR assays and 7 reactions of AF PCR tests were developed for postnatal and prenatal diagnosis, respectively. Assays were validated against routine tests in a blinded trial. Results The results showed 100% concordance with routine DNA PCR assays. Among 309 β-thalassemia carriers, 191 patients (61.8%) carried common β-thalassemia mutations. Among 448 AF specimens, 116 (25.9%) fetuses were found to be affected, 247 (55.1%) fetuses were carriers, and 85 (19%) fetuses were unaffected. Conclusion We found that WB and AF PCR assays are simple, rapid, and reliable. The developed techniques could be applicable in routine settings. [ABSTRACT FROM AUTHOR]

Introduction: Hemoglobin (Hb) analysis is a key testing for diagnosis of hemoglobinopathies. Accurate analysis, interpretation of results, and genetic risk assessment are important. We report on 8 years of the proficiency testing (PT) program for hemoglobinopathies in Thailand. Methods: Laboratory participants were required to test two simulated PT items in each cycle using capillary electrophoresis, one was a husband and another was his pregnant wife. Related hematological parameters were provided. The participants also provide interpretation and evaluate the risk of having three severe thalassemia diseases in an expected fetus. Three cycles were operated per year in accordance with the ISO17043 and ISO13528 guidelines. A total of 84 laboratories throughout Thailand were participated. Results: A total of 24 PT cycles were performed during 2012‐2019. Most participants had Excellent performance for the PT items with normal, β‐thalassemia trait, hemoglobin E trait, hemoglobin E trait with α‐thalassemia, and Hb H disease. However, when the PT items with homozygous Hb E and Hb E‐β‐thalassemia were tested, an increase in a Needs improvement performance was noted. From 24 PT cycles, the performance with Excellent, Good, Fair, and Needs improvement was ranging from 10.5%‐95.8%, 0%‐11.3%, 0%‐77.2%, and 2.3%‐37.0%, respectively. Conclusion: Most participants have proven their performance to be reliable and demonstrated their abilities to provide interpretation and genetic risk assessment on most of the PT items. For complex thalassemia however, a need to improve the interpretation and risk assessment skills is required which is essential for effective prevention and control of severe thalassemia diseases in Thailand. [ABSTRACT FROM AUTHOR]

Introduction: A high frequency of β‐thalassemia in Lao People's Democratic Republic necessitates the importance of complete molecular data before a prevention and control program could be established. Limited data are available for Lao PDR. We have now reported an extended information on the molecular basis of β‐hemoglobinopathies in this population. Methods: The study was done on 519 unrelated Laos subjects requested for thalassemia investigation. Hematological data were recorded. Hb profiles were obtained using a capillary electrophoresis system. α‐And β‐globin genotyping was performed using PCR and related techniques. Results: Among the 519 subjects, 287 (55.3%) were found to carry β‐hemoglobinopathies based on Hb and DNA analyses. These included Hb E carriers (n = 135), homozygous Hb E (n = 47), β‐thalassemia carriers (n = 70), Hb E‐β‐thalassemia (n = 25), homozygous β‐thalassemia (n = 4), heterozygous δβ0‐thalassemia (n = 2), and carriers of the β‐Hb variant (n = 3). Mutation analysis identified in addition to the Hb E, 8 different β‐thalassemia mutations including codon 17 (A‐T), codons 41/42 (‐TTCT), NT‐28 (A‐G), codons 71/72 (+A), IVS1‐1 (G‐T), 3.4 kb deletion, an initiation codon (T‐G) and IVS2‐654 (C‐T). Two δβ0‐thalassemia carriers (12.6 kb deletion) and three subjects with Hb Hope (β136GGT‐GAT) were identified. Hematological features associated with these β‐hemoglobinopathies were presented. Conclusion: β‐hemoglobinopathies in the Laos population is heterogeneous. This information is relevant for setting up a molecular diagnostics and can provide a basis for genetic counseling and enable prenatal diagnosis. [ABSTRACT FROM AUTHOR]

Non-transfusion-dependent thalassemia (NTDT) is associated with various forms of thalassemia and genetic modifiers. We report the molecular basis of NTDT in hemoglobin (Hb) E-β-thalassemia disease. This study was done in 73 adult patients encountered at the prenatal diagnosis center of Khon Kaen University, Northeast Thailand. Hematological parameters and Hb patterns were collected, and α- and β-globin gene mutations were determined. Multiple single-nucleotide polymorphisms (SNPs) including the rs7482144/Gγ-XmnI polymorphism, rs2297339, rs2838513, rs4895441, and rs9399137 in the HBS1L-MYB gene, rs4671393 and rs11886868 in the BCL11A gene, and G176AfsX179 in the KLF1 gene were examined. Five β0-thalassemia mutations and a severe β+-thalassemia mutation in trans to the βE gene were identified. No significant difference in hematological parameters was observed among β-thalassemia genotypes. Coinheritance of α-thalassemia was observed in 31 of the 73 subjects (42.5%). Four SNPs including Gγ-XmnI, rs2297339, rs4895441, and rs9399137 of HBS1L-MYB were found to be associated with high Hb F levels in 39 (53.4%) subjects. The molecular basis of NTDT in the remaining 3 (4.1%) cases could not be defined. These results indicate multiple genetic factors in NTDT patients and underline the importance of complete genotyping to provide proper management, make clinical predictions, and improve genetic counseling. [ABSTRACT FROM AUTHOR]

We describe hematologic and molecular characteristics of a hitherto undescribed interaction between the Filipino deletional β0-thalassemia with Hb E and α-thalassemia in a Thai family. This study was conducted during the prenatal screening of a pregnant Thai woman and her family members. A prenatal diagnosis was performed at her second pregnancy by amniocentesis. Laboratory investigations identified that the pregnant woman was Hb E heterozygote with α+-thalassemia, whereas her husband was a double heterozygote for the Filipino deletional β0-thalassemia and α+-thalassemia. Their affected son was a patient with a previously undescribed condition of Hb E-β0-thalassemia with α+-thalassemia. Both a combined gap-polymerase chain reaction (PCR) and allele-specific PCR were used successfully in the prenatal diagnosis, which identified an affected fetus with Hb E-β0-thalassemia without α+-thalassemia. Beta globin gene haplotype analysis indicated the same origin of this Filipino β0-thalassemia in Asian populations. [ABSTRACT FROM AUTHOR]

We determined the prevalence of the H63D and the IVS5#1G-A HFE mutations in 370 (169 males and 201 females) Thai thalassemia carriers and 201 normal subjects. While no IVS5#1G-A mutation was found, the H63D heterozygosity was identified in 5.5% (11/201) of normal subjects and 7.3% (27/370) of thalassemia carriers. Within the thalassemic group, the medians (ranges) of serum ferritin were 217.5 ng/ml (20.1–424.3) and 169.8 ng/ml (3.9–3,536.0) in male subjects and 30.4 ng/ml (11.9–130.7) and 49.3 ng/ml (0.6–931.0) in female subjects with (HD) and without (HH) H63D mutation, respectively. The proportions of subjects with elevated ferritin were found to be 37.5% (6/16) for HD and 14.0% (18/129) for HH in male and 0% (0/11) for HD and 3.0% (5/164) for HH in female subjects, respectively. Statistical analysis of all the data revealed no significant difference. Among 14 Hb E/β-thalassemia patients, no difference in hematological data as well as serum ferritin levels was observed between those with (HD) and without (HH) H63D mutation. Therefore, the H63D heterozygosity has no significant effect on the serum ferritin level and screening for this HFE mutation in thalassemic patients is not recommended. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: α0-thalassemia is the most severe form of α-thalassemia alleles found among Southeast Asian and Chinese populations and can cause a fatal condition known as hemoglobin Bart's hydrops fetalis and hemoglobin H disease. In order to provide the molecular epidemiological characteristic of α0-thalassemia in northeast Thailand, a total of 12,525 blood specimens referred to our center at Khon Kaen University in northeast Thailand during October 2008 to January 2012 were studied. Hematological parameters were recorded and DNA deletions causing α0-thalassemia were examined by PCR related techniques. Among 12,525 samples examined, α0-thalassemia alleles were identified in 1,873 (15.0%) samples, including 1855 (14.8%) cases with Southeast Asian (−−SEA) deletion and 18 cases (0.2%) with THAI deletion (−−THAI). As many as twenty genotypes were encountered. Hb profiles and hematological parameters were comparatively presented. Data on prevalence, molecular features and phenotypic expression of α0-thalassemia should prove useful in a carrier screening and a prevention and control program of this common genetic disorder in the region. [Copyright &y& Elsevier]

Introduction: Thalassemia screening program has been implemented for years in Southeast Asia, but no external quality assessment program has been established. We have developed and initiated the proficiency testing (PT) program for the first time in Thailand with the aim to assess the screening performance of laboratory staff and their competency in interpretation of the screening results. Materials and methods: Three PT cycles per year were organized. From the first to the third cycle of the PT scheme, a total number of participant laboratories increased from 59 to 67. In each cycle, 2 PT items (assigned as blood samples of the couple) were provided. Performance evaluation was based on the accuracy of screening results, i.e. mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and the dichlorophenolindophenol (DCIP) test for haemoglobin E, including the competency in interpretation of screening results and assessment of foetal risk. Performance was assessed by comparing the participants' result against the assigned value. Results: Of all 3 cycles, most laboratories reported acceptable MCV and MCH values. From the first to the third cycle, incorrect DCIP test and misinterpretation rates were decreased while incorrect risk assessment varied by cycle to cycle. Combining the accuracy of thalassemia screening and the competency in interpretation and risk assessment, approximately half of participants showed excellent performance. Conclusion: Improved performance observed in many laboratories reflects the achievement and benefit of the PT program which should be regularly provided. [ABSTRACT FROM AUTHOR]

Abstract: Study on the phenotypic expression of hemoglobin (Hb) A2 and Hb E in Hb E disorders has been difficult due to the co-separation of Hb A2 and Hb E in most Hb analysis assays. Because these two Hbs are separated on capillary electrophoresis, we studied phenotypic expression of Hbs A2, 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 A2 of 2.7±0.3%. Heterozygous Hb E and homozygous Hb E had elevated Hb A2 i.e. 3.8±0.3% and 4.8±0.5%, respectively. Further elevations were observed for β0-thalassemia/Hb E (6.1±1.9%) and β+-thalassemia/Hb E (7.1±1.2%). Interestingly, no elevation of Hb A2 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 A2 were not altered. Different phenotypic expression of Hb A2, 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. [Copyright &y& Elsevier]

BACKGROUND Mutations in the FLT3 gene are associated with acute myeloid leukemia (AML). FLT3 mutations have been identified in approximately 30% of de novo AML patients, particularly those with typical karyotype and inferior prognosis. Therefore, we examined the frequencies of an internal tandem duplication (ITD) and missense mutations of the FLT3 gene and their associated clinical characteristics in patients with AML in northeast Thailand. MATERIAL AND METHODS The leftover bone marrow and/or peripheral blood specimens of 65 newly diagnosed AML patients recruited from Srinagarind Hospital, Khon Kaen University, northeast Thailand, between January 2020 and May 2021 were included in this study. FLT3-ITD and FLT3- tyrosine kinase domain (TKD) were amplified using PCR-related techniques. RESULTS The frequencies of FLT3-ITD and TKD were found to be 16.9% (11/65) and 10.8% (7/65), respectively. One patient had ITD and TKD mutations. The white blood cell count and peripheral blast percentage of FLT3-ITD-positive patients were statistically significantly higher than those of the FLT3-wild type patients, while the peripheral blast percentage of FLT3-TKD-positive patients was significantly lower. No other clinical characteristics among FLT3-positive and FLT3-wild-type patients were observed. DNA sequencing identified 4 FLT3-TKD mutations. The c.2504A>T; Asp835Val and c.2503G>C; Asp835His mutations were predicted as pathogenic mutations while the 2 novel mutations, c.2508C>A; Ile836= and c.2508C>G; Ile836Met were predicted as neutral mutations. CONCLUSIONS This study showed for the first time that FLT3-TKD mutation is common among northeast Thai AML patients. The data should prove useful for selecting efficacious targeted treatment plans for the patients.

Objective: The degree of ineffective erythropoiesis is known to be associated with clinical severity among individuals with thalassemia. The association of ineffective erythropoiesis biomarker levels with different thalassemia genotypes, however, remains limited. The aim of this study was to explore the level of phosphatidylserine-exposed red blood cells (PS-exposed RBCs) and ineffective erythropoiesis biomarkers (growth-differentiation factor-15 and soluble transferrin receptors) in patients with different genotypes., Methods: A cross-sectional study was conducted on 139 patients of age 18 years and above with different genotypes at Srinagarind Hospital, Khon Kaen University, Thailand. The levels of PS-exposed RBCs were determined using flow cytometry. Measurements of growth-differentiation factor-15 (GDF-15) and soluble transferrin receptors (sTfR) were evaluated by the ELISA method., Results: The PS-exposed RBCs levels were found to be significantly higher in splenectomized beta-thalassemia patients. Patients with beta-thalassemia had the highest GDF-15 levels, followed by patients with non-deletional alpha-thalassemia. Patients with non-deletional alpha-thalassemia showed elevated hemoglobin levels and reduced GDF-15 levels after splenectomy. Patients with beta-thalassemia and non-deletional alpha-thalassemia had the highest levels of PS-exposed RBCs and ineffective erythropoiesis biomarkers, which correlated with the clinical severity of thalassemia., Conclusions: The levels of ineffective erythropoiesis biomarkers were different across thalassemia genotypes. Splenectomy may improve clinical symptoms of patients with non-deletional alpha thalassemia but not of patients with beta-thalassemia. These findings demonstrate differences in the degree of ineffective erythropoiesis in thalassemia, which emphasizes the need for different treatment approaches among patients with different thalassemia genotypes., Competing Interests: None., (AJTR Copyright © 2022.)

Objectives: A co-inheritance of α 0 -thalassemia can ameliorate the clinical severity of the hemoglobin (Hb) E-β-thalassemia disease. This information should be provided at prenatal diagnosis. Identification of α 0 -thalassemia in an affected fetus is therefore valuable. We have explored this genetic interaction in a large cohort of affected fetuses with hemoglobin (Hb) E-β-thalassemia in northeast Thailand., Methods: A study was done retrospectively on 1,592 couples at risk of having fetuses with Hb E-β 0 -thalassemia, encountered from January 2011 to December 2019. A total of 415 left-over DNA specimens of the affected fetuses with Hb E-β 0 -thalassemia disease were further investigated. Examination of α 0 -thalassemia was done using gap-PCR or a multiplex PCR assay for simultaneous detection of Hb E and α 0 -thalassemia mutations., Results: Of the 415 affected fetuses, the two most common β 0 -thalassemia genes found were the codons 41/42 (-TTCT) (199/415; 48.0%) and codon 17 (A-T) (115/415; 27.7%). α 0 -thalassemia was found unexpectedly in 21 (5.1%) fetuses. Hematologic phenotypes of the parents indicated that it was impossible to differentiate a pure β 0 -thalassemia carrier from a double β 0 -thalassemia/α 0 -thalassemia heterozygote unless DNA analysis is performed. In contrast, a reduced level of Hb E in the Hb E carrier (<25%) is a valuable marker for predicting double heterozygosity for Hb E/α 0 -thalassemia. This could be further confirmed using a multiplex PCR assay., Conclusions: There is a high prevalence of co-inheritance of α 0 -thalassemia in fetuses with Hb E-β 0 -thalassemia disease. In a high-risk population such as Thailand, we recommend screening for α 0 -thalassemia in all affected fetuses with Hb E-β 0 -thalassemia disease and providing complete genetic information to the parents to make appropriate decisions at prenatal diagnosis and genetic counseling., Competing Interests: None., (AJTR Copyright © 2022.)

Objective: Prenatal and postnatal diagnosis of hemoglobin E-β 0-thalassemia can be made using polymerase chain reaction (PCR) analysis mostly on purified DNA. We have establihed a direct amplification method without DNA extraction on whole blood (WB) and amniotic fluid (AF) specimens to diagnose the disease., Methods: Three reactions of WB PCR assays and 7 reactions of AF PCR tests were developed for postnatal and prenatal diagnosis, respectively. Assays were validated against routine tests in a blinded trial., Results: The results showed 100% concordance with routine DNA PCR assays. Among 309 β-thalassemia carriers, 191 patients (61.8%) carried common β-thalassemia mutations. Among 448 AF specimens, 116 (25.9%) fetuses were found to be affected, 247 (55.1%) fetuses were carriers, and 85 (19%) fetuses were unaffected., Conclusion: We found that WB and AF PCR assays are simple, rapid, and reliable. The developed techniques could be applicable in routine settings., (© American Society for Clinical Pathology, 2021. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Introduction: Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common X-linked enzymopathy, highly prevalent in the areas where malaria is or has been endemic. Prevalence of G6PD deficiency and characterization of G6PD variants in females from previously malaria-endemic areas of northeastern Thailand remain unstudied., Methods: Prevalence of G6PD deficiency was determined by a fluorescent spot test (FST), quantitative G6PD activity assay, and multiplex allele-specific (AS)- and restriction fragment length polymorphic (RFLP)-PCR developed for detection of common G6PD variants in the Thai population., Results: Prevalence of G6PD deficiency in female samples (n = 355) was 18% by FST, 29.6% by quantitation of G6PD activity, and 28.1% by PCR-based genotyping. The most common variant was G6PD Viangchan (54%), followed by G6PD Canton (11%) and G6PD Union (11%); in addition, a novel heterozygous variant, G6PD Khon Kaen (c.305T>C, p.F102S), was identified. The majority of heterozygotes expressed G6PD activity within the intermediate deficiency range (30-70% median of normal enzyme activity)., Conclusion: High prevalence of G6PD deficiency was present in females from northeastern Thailand, the majority being due to heterozygosity of G6PD variants. The findings will have a bearing on the inclusion of primaquine in antimalarial-based policies for malaria elimination in populations with a high prevalence of G6PD deficiency., Competing Interests: Competing interests: The authors declare no conflict of Interest.

Objectives: Southeast Asian ovalocytosis (SAO) is an inherited red blood cell (RBC) membrane disorder, whereas hemoglobinopathies are inherited globin gene disorders. In an area where both diseases are prevalent, the interaction between them resulting in variable hematologic parameters can be encountered. However, little is known about the genetic interaction of SAO and thalassemia. We investigated the prevalence of SAO and hemoglobinopathy genotypes among newborns in southern Thailand., Patients and Methods: This study was carried out on 297 newborns recruited consecutively at Naradhiwas Rajanagarindra Hospital in the south of Thailand. The SAO was identified on blood smear examination and polymerase chain reaction analysis. Thalassemia genotypes were defined. Hematologic parameters and hemoglobin (Hb) profiles were recorded and analyzed., Results: Among 297 newborns, 15 (5.1%) carried SAO, whereas 70 (23.6%) had thalassemia with 15 different thalassemia genotypes. Abnormal Hb including Hb C, Hb Q-Thailand, and Hb D-Punjab were observed in 5 newborns. It was found in the nonthalassemic newborns that RBC count, Hb, and hematocrit of the nonthalassemic newborns with SAO were significantly lower than those without SAO. The same finding was also observed in the thalassemic newborns; RBC count, Hb, and hematocrit of the thalassemic newborns with SAO were significantly lower than those without SAO. However, the mean corpuscular volume, mean corpuscular Hb, and RBC distribution width of the SAO-newborns were significantly higher., Conclusions: Both SAO and hemoglobinopathy genotypes are common in southern Thailand. One should take this into consideration when evaluating neonatal anemia and other hematologic abnormalities. Identification of both genetic defects and long-term monitoring on the clinical outcome of this genetic interaction should be essential to understand the pathogenesis of these common genetic disorders in the region., Competing Interests: The authors declare no conflict of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The finding of many Thai Hb E-β 0 -thalassemia patients with non-transfusion dependent thalassemia (NTDT) phenotype without co-inheritance of α-thalassemia has prompted us to investigate the existence of other genetic modifying factors., Methods: Study was done on 122 adult Thai patients with NTDT Hb E-β-thalassemia patients without co-inheritance of α-thalassemia. Multiple single-nucleotide polymorphisms (SNPs) associated with γ-globin gene expression including the G γ- Xmn I of HBG2 gene, rs2297339, rs4895441, and rs9399137 of the HBS1L-MYB gene, rs4671393 in the BCL11A gene, and G176AfsX179, T334R, R238H and -154 (C-T) in the KLF1 gene were investigated using PCR and related techniques., Results: Heterozygous and homozygous for G γ- Xmn I of HBG2 gene were detected at 70.5% and 7.4%, respectively. Further DNA analysis identified the rs2297339 (C-T), rs4895441 (A-G), and rs9399137 (T-C) of HBS1L-MYB gene in 86.9%, 25.4%, and 23.0%, respectively. The rs4671393 (G-A) of the BCL11A gene was found at 31.2%. For the KLF1 gene, only T334R was detected at 9.0%., Conclusions: It was found that these SNPs, when analyzed in combination, could explain the mild phenotypic expression of all cases. These results underline the importance of these informative SNPs on phenotypic expression of Hb E-β-thalassemia patients., Competing Interests: Competing interests: The authors have declared that no competing interests exist.

Hemoglobin Bart's hydrops fetalis (homozygous α 0 -thalassemia) is the most severe form of thalassemia in the Southeast Asian population. Fetuses with this disorder almost always die in utero or shortly after birth. Screening of α 0 -thalassemia carrier is therefore crucial. Currently, diagnosis of α 0 -thalassemia genes is done by DNA-based analysis which relies on DNA extraction. We have developed a simple screening format based on whole blood PCR assay. The method was validated on 198 specimens and the results show 100% concordance with a conventional gap-PCR on DNA specimens. The protocol could also be applied to amniotic fluid specimens in prenatal diagnostic testing. The assay developed should facilitate carrier screening and prenatal diagnosis of Hb Bart's hydrops fetalis syndrome in the region., (© 2018 by the Association of Clinical Scientists, Inc.)