Showing papers on "Hemoglobin A2 published in 2021"
TL;DR: In this article, an extensive molecular characterization of δ-hemoglobinopathies in Thailand has been performed on 32,108 subjects, encountered at the thalassemia screening.
Abstract: The δ-globin gene defects are clinically silent but interaction with β-thalassemia can lead to a misdiagnosis of β-thalassemia carrier. We report an extensive molecular characterization of δ-hemoglobinopathies in Thailand. Study was done on 32,108 subjects, encountered at the thalassemia screening. Six different approaches based on the reduced Hb A2 or appearance of Hb A2-derivative were established for selective recruitment of subjects. Among 32,108 subjects, a total of 296 subjects were suspected of having δ-globin gene defects. Of these 296 subjects, Hb and DNA analyses identified δ-hemoglobinopathies with 10 different mutations in 34 (0.11%) of them. These included a novel mutation, [δCD30(AGG>GGG) (n = 1)], 5 previously undescribed in Thailand, [δ-44(G>A) (n = 7), Hb A2-Troodos (n = 5), δIVSII-897(A>C) (n = 4), δ-68(C>T) (n = 2), and Hb A2-Indonesia (n = 1)], and 4 mutations previously found in Thailand, [Hb A2-Melbourne (n = 9), δ-77(T>C) (n = 3), Hb A2' (n = 1), and Hb A2-Kiriwong (n = 1)]. Genetic heterogeneities seen included interactions of δ-globin gene defects with heterozygous Hb E, β-thalassemia, α-thalassemia, and in cis locations of the Hb A2-Troodos and Hb E mutations found for the first time. Rapid identification methods of these δ-globin gene mutations were developed. The results should prove useful to a prevention and control program of hemoglobinopathies in the region.
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Journal Article•
TL;DR: In this article, the authors conducted a laboratory-based retrospective study for a period of two years from January 1, 2013 to December 31, 2014 in the Government Medical College, Jammu.
Abstract: Introduction: Haemoglobinopathies are major public health problems in India. Haemoglobinopathies are inherited single gene disorders having abnormal globin protein. Genes in ?-globin and β-globin genes clusters (on chromosomes 16 and 11) control globin chain production. Due to spontaneous mutation in globin genes haemoglobin variants are produced.
Disorders range from thalassemia to many hemoglobin variants with no, mild or severe consequences for the carrier.
Materials and Method: The present laboratory-based retrospective study was conducted for a period of two years from January 1, 2013 to December 31, 2014 in the Government Medical College, Jammu. Data of 543 patients who had come to the laboratory for their hemoglobin electrophoresis was compiled and studied. Complete blood count was carried out on HMX (Beckman Coulter) and hemoglobin electrophoresis for diagnosing any abnormal hemoglobin disorder was done on D10 (BIO RAD).
Results: Out of 543 patients, 368 (67.77%) were normal and 175 (32.23%) had abnormal hemoglobin pattern. Spectrum of haemoglobinopathies prevalent in descending order were 13.99% β-thalassemic trait, 6.26% ?-thalassemic trait, 4.6% elevated fetal haemoglobin, 2.57% false elevation of hemoglobin A2 because of mean corpuscular volume, 1.29% β-thalassemic major, 0.93% haemoglobin S homozygous, 0.74% borderline hemoglobin A2, 0.55% patients were with other type of hemoglobinopathies.
Conclusion: High prevalence of haemoglobinopathies in Jammu division makes the disease a major public health problem in our population. Population screening, genetic counseling and prenatal diagnosis can prevent these genetic disorders.
Keywords: Haemoglobinopathies, Thalassemia, Anaemia, beta thalassemia, Jammu
TL;DR: In this article, the authors described eight new δ-globin gene variants discovered and characterized in some laboratories in Northern Italy in recent years, which were added to the many already known Hb A2 variants that were found with an estimated frequency of about 1-2% during the screening tests in their laboratories.
Abstract: Background: Hemoglobin A (Hb A) (α2β2) in the normal adult subject constitutes 96–98% of hemoglobin, and Hb F is normally less than 1%, while for hemoglobin A2 (Hb A2) (α2δ2), the normal reference values are between 2.0 and 3.3%. It is important to evaluate the presence of possible delta gene mutations in a population at high risk for globin gene defects in order to correctly diagnose the β-thalassemia carrier. Methods: The most used methods for the quantification of Hb A2 are based on automated high performance liquid chromatography (HPLC) or capillary electrophoresis (CE). In particular Hb analyses were performed by HPLC on three dedicated devices. DNA analyses were performed according to local standard protocols. Results: Here, we described eight new δ-globin gene variants discovered and characterized in some laboratories in Northern Italy in recent years. These new variants were added to the many already known Hb A2 variants that were found with an estimated frequency of about 1–2% during the screening tests in our laboratories. Conclusions: The knowledge recognition of the delta variant on Hb analysis and accurate molecular characterization is crucial to provide an accurate definitive thalassemia diagnosis, particularly in young subjects who would like to ask for a prenatal diagnosis or preimplantation genetic diagnosis.