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Hemoglobin disorders are among the most common genetic diseases worldwide. Molecular diagnosis is helpful in cases where the diagnosis is uncertain and for genetic counseling. Protein‐based diagnostic techniques are frequently adequate for initial diagnosis. Molecular genetic testing is pursued in some cases, particularly when a definitive diagnosis is not possible and especially for the purpose of assessing genetic risk for couples wanting to have children. The expertise available in the clinical hematology laboratory is essential for the diagnosis of patients with hemoglobin abnormalities. Initial diagnoses are made using protein‐based techniques such as electrophoresis and chromatography. Based on these findings, genetic risk to an individual's offspring can be assessed. In the setting of β‐thalassemia and other β‐globin disorders, coincident α‐thalassemia may be difficult to diagnose, which can have potentially serious consequences. In addition, unusual forms of β‐thalassemia caused by deletions in the β‐globin locus cannot be definitively characterized using standard techniques. Molecular diagnostic testing has an important role in the diagnosis of hemoglobin disorders and is important in the setting of genetic counseling. Molecular testing also has a role in prenatal diagnosis to identify fetuses affected by severe hemoglobinopathies and thalassemias. [ABSTRACT FROM AUTHOR]

Background: Antenatal screening is vital to identifying couples at risk of having children with a clinically significant haemoglobinopathy. In Australia, immigration is increasing carrier incidence. Methods: A retrospective analysis was performed of full blood count, high-performance liquid chromatography and haemoglobin electrophoresis of women and their partners who underwent antenatal haemoglobinopathy screening over three years at a major NSW laboratory. Genetic testing results were included where available. Results: One thousand six hundred and twenty-eight women and 729 male partners were screened at a median gestation of 14 weeks. 8.2% of women had a clinically significant result, with a median 16-day interval to partner testing. In 35% of couples screened simultaneously, the partner did not require testing. Genetic confirmatory testing was performed in 65% of high risk couples. Conclusion: There was a significant delay to antenatal haemoglobinopathy screening for mothers, limiting time for genetic diagnosis, prenatal diagnosis and management of affected pregnancies. Screening should be performed earlier. Simultaneous couple testing is not cost-effective. [ABSTRACT FROM AUTHOR]

Aim: To know the patterns of hemoglobinopathies and their prevalence in Kerbala society by using high performance liquid chromatography and to conclude if there is any correlations between different hematological parameters in Hemoglobinopathy patients. A total of 70 cases studied from 16th of February 2018 to 20th of June 2018 for hemoglobin variant analysis at the teaching labrotarioes of Al- Hussseini Teaching hospital which were studied for patterns of hemoglobinopathies. When the samples were received, Complete Blood Counts including: Hemoglobin concentration, Total White blood cells count (WBC), Mean Cell Volume (MCV), Mean Cell Haemoglobin (MCH), Mean Cell Hemoglobin Concentration (MCHC), Serum ferritin, Total Iron Binding Capacity ( TIBC), Hemoglobin H (HbH) preparation were done. Out of total 70 patients screened for patterns of hemoglobinopathies the result of the study revealed that 48 Patients which represent(68.57 %) of total patients had B-thalassemia trait which form the predominant percentage of patients with haemoglobinopathy, 11.85% of patients had sickle cell trait, 5.71% of them had B-Thalassemia Major, 4.29% had Hb S/B+Thalassemia Trait, 2.86% had HbS/Alpha thalassemia trait, 1.43% of them had Hb S homozygosity, 1.43% Alpha thalassemia trait, 1.43% had D-Los Anglos, 1.43% had HbS/B+ Thalassemia trait and 1.43% had HbC/B-Thalassemia trait. [ABSTRACT FROM AUTHOR]

Introduction: The hemoglobinopathies pose a significant health burden in India. Apart from the β thalassemias and sickle cell disorders, α thalassemias and structural hemoglobin variants are also common. Here we have reviewed the phenotypic and molecular diversity of hemoglobinopathies encountered at a referral center in western India over a period of 15 years. Materials and Methods: Screening for hemoglobinopathies was done using HPLC and cellulose acetate electrophoresis. Molecular characterization was done using Covalent Reverse Dot Blot Hybridization (CRDB), Amplification Refractory Mutation System (ARMS), GAP PCR and direct DNA sequencing. Results: The study includes 31 075 individuals who were referred for diagnosis of hemoglobinopathies and prenatal diagnosis. Of these 14 423 individuals showed various hemoglobin abnormalities. Beta genotyping in 5615 individuals showed the presence of 49 β thalassemia mutations. 143 β thalassemia heterozygotes had normal or borderline HbA2 levels. We identified three δ gene mutations (HbA2 Pellendri, HbA2 St.George, HbA2 Saurashtra) in β thalassemia heterozygotes leading to normal HbA2 levels. The commonest defects among the raised Hb F determinants were Gγ(Αγδβ)0 Indian inversion and the HPFH‐3 Indian deletion. A total of 312 individuals showed the presence of α thalassemia, of which 12.0% had a single α gene deletion (−α/αα). HbH disease was identified in 29 cases with 10 different genotypes. Alpha globin gene triplication was seen in 2.1% of β thalassemia heterozygotes with a thalassemia intermedia phenotype. Seven unusual α chain variants and eight uncommon β chain variants were identified. Conclusion: The repertoire of molecular defects seen in the different globin genes will be valuable for management and control of these disorders both in India as well as in other countries where there is a huge influx of migrant populations from India. [ABSTRACT FROM AUTHOR]

Hemoglobinopathies are one of the major problems in Pakistan. A retrospective analysis of blood samples of 2731 patients from 2010 to 2014 was done at National Institute of Blood Disease & Bone Marrow Transplantation for the workup of anemia or other blood-related disorders. Whole blood samples in EDTA were collected; complete blood counts with peripheral smears were prepared. Hemoglobin (Hb) electrophoresis on Genio was performed at alkaline pH. Samples showing borderline results were further tested by high-performance liquid chromatography or for specific mutation analysis by ARMS-PCR. Out of total 2731, 935 (34.2%) patients had hemoglobinopathies. Out of these 935 patients who had hemoglobinopathies, beta thalassemia minor 51.8%, beta thalassemia major 24.1%, HbD trait 6.7, sickle/ beta thalassemia 4.5%, sickle cell disease 3.9%, HbE trait 1.9%, and sickle cell trait 1.7% were most common hemoglobinopathies. Less prevalent were delta/beta thalassemia, HbE homozygous, HbD homozygous, and HbH disease. [ABSTRACT FROM AUTHOR]

Background HbA1c is used in the diagnosis and monitoring of diabetes mellitus (DM). Interference from hemoglobin variants is a well-described phenomenon, particularly with HPLC-based methods. While immunoassays may generate more reliable HbA1c results in the presence of some variants, these methods are susceptible to negative interference from high concentrations of HbF. We report a case where an accurate HbA1c result could not be obtained by any available method due to the presence of a compound hemoglobinopathy. Methods HbA1c was measured by HPLC, immunoassay, and capillary electrophoresis. Hemoglobinopathy investigation consisted of a CBC, hemoglobin fractionation by HPLC and electrophoresis, and molecular analysis. Results HbA1c analysis by HPLC and capillary electrophoresis gave no result. Analysis by immunoassay yielded HbA1c results of 5.9% (Siemens DCA 2000 +) and 5.1% (Roche Integra), which were inconsistent with other markers of glycemic control. Hemoglobinopathy investigation showed HbC with the hereditary persistence of fetal hemoglobin-2 Ghana deletion. Conclusion Reliable HbA1c results may be unobtainable in the presence of some hemoglobinopathies. HPLC and capillary electrophoresis alerted the laboratory to the presence of an unusual hemoglobinopathy. Immunoassays generated falsely low results without warning, which could lead to missed diagnoses and under treatment of patients with DM. [ABSTRACT FROM AUTHOR]

Background The World Health Organization and the American and Canadian Diabetes Associations approved HbA1c > 6.5% as diagnostic for type 2 diabetes mellitus (T2DM). Hb variants and/or their chemically modified species can interfere with HbA1c measurements. We recently described a patient with Hb Wayne trait who was misdiagnosed with T2DM based on falsely elevated HbA1c. Hb Wayne is a clinically silent variant that exists as two isoforms: Hb Wayne I (Asn 139) and Hb Wayne II (Asp 139). Methods Hemoglobinopathy investigation was performed by HPLC (Bio-Rad VARIANT-II), alkaline and acid electrophoresis (Sebia Hydrasis2), capillary zone electrophoresis (Sebia CAPILLARYS2™) and DNA sequencing. HbA1c was measured by five methods. Results Hb Wayne eluted as two small fractions with retention times of 1.0 and 1.46 min on the HPLC (Bio-Rad VARIANT-II). Alkaline gel and capillary electrophoresis showed two small bands migrating faster than HbA. Hb Wayne generated spuriously high results on the Bio-Rad VARIANT-II Turbo 2.0, no results on the Tosoh G8, and did not interfere with either the Sebia CAPILLARYS2™ or immunoassays from Roche (tinaquant) and Siemens (Bayer DCA2000 +). Based on the Hb Wayne HPLC profile of 3 patients, an algorithm was developed to facilitate its detection, which identified 9 additional patients with Hb Wayne trait. Conclusions We characterize Hb Wayne by chromatographic and electrophoretic techniques and show the effect of Hb Wayne on five common HbA1c methodologies. We developed a quality assurance tool to assist in detecting Hb Wayne trait during HbA1c analysis on the Bio-Rad VARIANT-II™ Turbo 2.0. [ABSTRACT FROM AUTHOR]

Introduction Capillary zone electrophoresis (CZE) at alkaline pH is one of the techniques used for hemoglobinopathy screening. In this study, an evaluation of the performance of a lower throughput CZE instrument, the Sebia Minicap Flex Piercing system, for this purpose is reported for the first time. Methods The analytical performance of the Sebia Minicap Flex Piercing system was evaluated. Furthermore, a method comparison between the Sebia Minicap Flex Piercing and two HPLC methods, that is, the Bio-Rad Variant Classic™ and the Bio-Rad D-10™ systems was performed by measuring samples with and without clinically relevant hemoglobin disorders. Results The analytical performance was acceptable for the determination of HbA, HbA2, HbS, and HbF, with an imprecision ≤2.0%. Method comparison showed a linear correlation for HbA2, HbF, and HbS measurements. Clinical concordance was acceptable when comparing CZE and HPLC. Conclusions Lower throughput CZE using the Sebia Minicap Flex Piercing can be used for precise and accurate first line screening and follow-up of hemoglobinopathies. [ABSTRACT FROM AUTHOR]