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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]

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]

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: 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]

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.)

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.)

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.)