Haemoglobin Fontainebleau (HBA2: c. 64G>C) in Oman: molecular and haematological characteristics and interaction with various haemoglobinopathies

2017 ◽  
Vol 71 (4) ◽  
pp. 303-308
Author(s):  
Shahina Daar ◽  
Shoaib Al Zadjali ◽  
Salam Alkindi ◽  
Yasser Wali ◽  
Abdulhakeem Al-Rawas ◽  
...  

ObjectivesTo describe the laboratory features of haemoglobin Fontainebleau (Hb FB) and its interactions with various α and β globin gene mutations in the Omani population.MethodsOver a period of 10 years, a total of 94 blood samples were suspected to have an α variant on HPLC at the Sultan Qaboos University Hospital, Muscat, Oman. Molecular testing was performed using PCR based techniques to define the variant and to analyse other interacting mutations in either α or β globin genes.ResultsOf 94 subjects, molecular analysis confirmed the Hb FB variant in 55 samples (38 non-cord and 17 cord blood). A total of 36/38 non-cord samples were heterozygous for the variant, while all 17 cord blood samples were heterozygotes. A total of 43/55 individuals had a concomitant α and/or β globin gene mutation.ConclusionsHb FB is the the most common α variant in the Omani population. We report the different HPLC profiles of this variant that we observed, with and without other haemoglobinopathies in non-cord and cord blood samples. This is the first report describing the HPLC profiles of this α globin chain variant on 1 year follow-up testing of cord blood samples. With careful analysis by HPLC, it is possible not only to identify Hb FB but also to predict any concomitant α and/or β globin gene mutations.

Blood ◽  
1982 ◽  
Vol 59 (2) ◽  
pp. 370-376 ◽  
Author(s):  
LE Lie-Injo ◽  
A Solai ◽  
AR Herrera ◽  
L Nicolaisen ◽  
YW Kan ◽  
...  

Abstract The white blood cell DNA of 36 cord blood samples with Hb Bart's in the red blood cells was studied for alpha-globin gene deletions by hybridization of DNA fragments digested by the restriction endonucleases Eco RI, Hpa I, Bam HI, and Bgl II. All 16 DNA samples from cord blood with Hb Bart's below 3% and no other abnormal hemoglobin had one alpha-globin gene deletion (alpha thal2), except one which had two alpha-globin gene deletions (alpha thal1). Most of the alpha thal2 were of the rightward deletion alpha thal2 genotype. Two new types of alpha thal2 variation was found, probably due to a polymorphism somewhere in an area outside the alpha-globin gene. All 14 cases with Hb Bart's between 3.5% and 8.5% and no other abnormal hemoglobin had two alpha-globin gene deletions (alpha thal1), except one that did not have any alpha-globin gene deletion and one that had one alpha-globin gene deletion. Three DNA samples of cord blood with Hb Bart's accompanied by Hb CoSp did not have any alpha-globin gene deletion. Sixty-five DNA samples from cord blood without Hb Bart's or other abnormal hemoglobin had no alpha-globin gene deletions, except one that had one alpha-globin gene deletion (alpha thal2). Two of the 65 DNA samples were found to have triplicated alpha-globin gene loci.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 1865-1865
Author(s):  
Seung-Jae Noh ◽  
Samuel Miller ◽  
Y. Terry Lee ◽  
Francesco M. Marincola ◽  
David Stroncek ◽  
...  

Abstract MicroRNAs are ~22nt-long small noncoding RNAs that negatively regulate expression of target proteins through mRNA degradation or translational repression. They are functionally important in diverse biological processes including development, oncogenesis, and hematopoiesis. To study a potential role of microRNA for regulating cellular changes during erythroid ontogeny, we examined microRNA abundance patterns in circulating erythroid cells during the fetal and adult stages of human development. Expression profiling of microRNA was performed using total RNA from 4 adult peripheral blood samples compared to 4 cord blood samples after depletion of plasma, platelets, and nucleated cells. Labeled RNA was hybridized to custom spotted array containing 474 human microRNAs species (miRBase release 9.1). Total RNA from Epstein-Barr virus (EBV)-transformed lymphoblastoid cell lines was used as a hybridization reference for all samples to generate microRNA abundance profile for each sample. Among the differentially expressed probe-pairs, 40 microRNAs were significantly up-regulated in adult erythroid cells and only 4 microRNAs were down-regulated (p < 0.01 and fold change > 2). Two microRNAs, miR-144 and miR-451, previously reported as being GATA-1 regulated in erythroid cells, were detected above the dynamic range of the array technology in all eight samples. Quantitative PCR was performed to further quantitate differences in the microRNA abundance profiles of the 10 most differentially expressed microRNAs as well as miR-144 and miR-451. Per published recommendations, miR-103 was used for signal normalization. Among the studied microRNAs, 8 of 12 demonstrated a more than 4 fold increase in abundance in adult erythroid cells compared to cord blood by qPCR. In particular, let-7d and let-7e demonstrated more than 10-fold increased expression in adult cells. Of note, let-7 microRNAs regulate metamorphic processes in model organisms and inhibit ras-associated growth of cancer cells. According to miRBase predictions, over 1200 genes may be targeted by the 8 microRNAs (p < 0.001). Examination of cord and adult reticulocyte mRNA expression profiles (Goh et al. Phy. Gen. 2007) revealed 24 developmentally downregulated genes as predicted targets. Among globin genes, only gamma globin is a predicted target. These findings demonstrate dramatic up-regulation of specific erythroid microRNAs during the fetal-to-adult transition of ontogeny, and support the notion that microRNAs function as developmental regulators of erythropoiesis and globin gene switching.


Blood ◽  
1982 ◽  
Vol 59 (2) ◽  
pp. 370-376
Author(s):  
LE Lie-Injo ◽  
A Solai ◽  
AR Herrera ◽  
L Nicolaisen ◽  
YW Kan ◽  
...  

The white blood cell DNA of 36 cord blood samples with Hb Bart's in the red blood cells was studied for alpha-globin gene deletions by hybridization of DNA fragments digested by the restriction endonucleases Eco RI, Hpa I, Bam HI, and Bgl II. All 16 DNA samples from cord blood with Hb Bart's below 3% and no other abnormal hemoglobin had one alpha-globin gene deletion (alpha thal2), except one which had two alpha-globin gene deletions (alpha thal1). Most of the alpha thal2 were of the rightward deletion alpha thal2 genotype. Two new types of alpha thal2 variation was found, probably due to a polymorphism somewhere in an area outside the alpha-globin gene. All 14 cases with Hb Bart's between 3.5% and 8.5% and no other abnormal hemoglobin had two alpha-globin gene deletions (alpha thal1), except one that did not have any alpha-globin gene deletion and one that had one alpha-globin gene deletion. Three DNA samples of cord blood with Hb Bart's accompanied by Hb CoSp did not have any alpha-globin gene deletion. Sixty-five DNA samples from cord blood without Hb Bart's or other abnormal hemoglobin had no alpha-globin gene deletions, except one that had one alpha-globin gene deletion (alpha thal2). Two of the 65 DNA samples were found to have triplicated alpha-globin gene loci.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Xi Luo ◽  
Xiang-mei Zhang ◽  
Liu-song Wu ◽  
Jindong Chen ◽  
Yan Chen

Abstract Background α-thalassemia is relatively endemic in Guizhou province of southwestern China. To predict the clinical manifestations of α-globin gene aberration for genetic counseling, we examined the prevalence of the α-globin triplication and the genotype–phenotype correlation in this subpopulation Methods A cohort of 7644 subjects was selected from nine ethnicities covering four regions in Guizhou province of China. Peripheral blood was collected from each participant for routine blood testing and hemoglobin electrophoresis. PCR-DNA sequencing and Gap-PCR were used to identify the thalassemia gene mutations. Chi-square tests and one-way analysis of variance (ANOVA) were used to statistically analyze the data. Results We found that the frequency of α-globin triplication in Guizhou province was 0.772% (59/7644). Genotypically, the αααanti4.2/αα accounted for 0.523% (40/7644), the αααanti3.7/αα for 0.235% (18/7644), and the αααanti3.7/–SEA for 0.013% (1/7644). The αααanti4.2/αα is more prevalent than the αααanti3.7/αα in Guizhou. In addition, the frequency of the HKαα/αα (that by GAP-PCR is like αααanti4.2/-α3.7) was 0.235% (18/7644). Ethnically, the Tujia group presented the highest prevalence (2.47%) of α-globin triplication. Geographically, the highest frequency of the α-globin triplication was identified in Qiannan region (2.23%). Of the triplicated α-globin cases, 5 coinherited with heterozygote β-thalassemia and presented various clinical manifestations of anemia. Conclusions These data will be used to update the Chinese triplicated α-globin thalassemia database and provide insights into the pathogenesis of thalassemia. These findings will be helpful for the diagnosis of thalassemia and future genetic counseling in those regions.


2020 ◽  
Vol 37 (12) ◽  
pp. 1280-1282
Author(s):  
Lorraine E. Toner ◽  
Shari E. Gelber ◽  
Juan A. Pena ◽  
Nathan S. Fox ◽  
Andrei Rebarber

Introduction Data regarding transplacental passage of maternal coronavirus disease 2019 (COVID-19) antibodies and potential immunity in the newborn is limited. Case Report We present a 25-year-old multigravida with known red blood cell isoimmunization, who was found to be COVID-19 positive at 27 weeks of gestation while undergoing serial periumbilical blood sampling and intrauterine transfusions. Maternal COVID-19 antibody was detected 2 weeks after positive molecular testing. Antibodies were never detected on cord blood samples from two intrauterine fetal cord blood samples as well as neonatal cord blood at the time of delivery. Conclusion This case demonstrates a lack of passive immunity of COVID-19 antibodies from a positive pregnant woman to her fetus, neither in utero nor at the time of birth. Further studies are needed to understand if passage of antibodies can occur and if that can confer passive immunity in the newborn. Key Points


2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Selahaddin Tekeş ◽  
Diclehan Oral ◽  
Murat Söker ◽  
Selda Şimşek ◽  
Veysiye Hülya Uzel ◽  
...  

Abstract Objectives Hemoglobin disorders are quite heterogeneous in the Turkish population. Up to now, more than forty different beta thalassemia mutations and 60 hemoglobin variants have been characterized in the country. The aim of this study was to investigate genetic heterogeneity of HBB gene mutations in patients and their parents at Southeastern Anatolia in Turkey. Methods Genomic DNA was isolated from 145 thalassemic patients’ blood samples and their parents in this study. Ten different HBB gene mutations HBB:c.-80T>A, HBB:c.17_18delCT, HBB:c.25_26delAA, HBB:c.92+1G>A, HBB:c.92+5G>C, HBB:c.92+6T>C, HBB:c.93-21G>A, HBB:c.135delC, HBB:c.315+1G>A, HBB:c.316-106C>G were screened by amplification refractory mutation system. Four Hb variants and some rare beta thalassemia mutation were characterized by DNA sequencing. Results In this study, 97 homozygous and 48 compound heterozygous thalassemic patients were diagnosed by molecular genetic analyses. As a results, 18 β-thalassemia mutations and four abnormal hemoglobins; HBB:c.20A>T, HBB:c.364G>C, HBB:c.34G>A and HBB:c.208G>A were detected at Dicle University Hospital. Conclusions In the results, HBB:c.93-21G>A is the most common mutation in the region. Three mutations [(HBB:c.93-21G>A), (HBB:c.25_26delAA) and (HBB:c.135delC)] account for about 58 per cent of all the point mutations. Except HBB:c.20A>T and HBB:c.364G>C, two silent Hb variants (HBB:c.34G>A and HBB:c.208G>A) were detected in this study. Hb Hamilton [β11 (GTT>ATT) Val>Ile] was seen first time in Turkey.


2019 ◽  
Vol 14 (03) ◽  
pp. 116-120
Author(s):  
Aysu Duyan Camurdan ◽  
Ufuk Beyazova ◽  
Gulendam Bozdayı ◽  
Fusun Civil ◽  
Aylin Altay Kocak ◽  
...  

Objective The objective of this study was to investigate the persistence of maternally derived antibodies to hepatitis A (anti-HAV) and varicella zoster (anti-VZV) viruses to determine the optimal time of vaccination of infants. Materials and Methods This study was conducted between 2011 and 2012 at the Gazi University Hospital. Blood samples were collected from healthy infants' cord blood and at 12th, 18th, and 24th months of age. Anti-HAV and anti-VZV immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies were measured by enzyme-linked immunosorbent assay kit in blood samples. Results A total of 546 infants and children were included in the study; all had blood samples taken at four time points (at birth [cord blood], and at 12, 18, and 24 months). Anti-HAV IgG seropositivity rates in these samples were 77.3, 29.6, 14.8, and 17.7%, respectively (p < 0.05). Corresponding anti-VZV IgG seropositivity rates were 83.3, 21.5, 29.5, and 33.8%, respectively (p < 0.05). Conclusion Anti-HAV and anti-VZV seropositivity rates were lowest at 18 and 12 months, respectively. We suggest that if VZV and hepatitis A vaccines were included in the national vaccination program after the age of 1 year, there should be little interference from passively acquired maternal antibodies.


2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Rawand P. Shamoon ◽  
Ahmed K. Yassin ◽  
Ranan K. Polus ◽  
Mohamad D. Ali

Abstract Background HbH disease results from dysfunction of three, less commonly two, α-globin genes through various combinations of deletion and non-deletion mutations. Characterization of the mutations and the underlying genotypes is fundamental for proper screening and prevention of thalassaemia in any region. The aim of this study was to explore the genetic arrangements of HbH disease and to correlate the genotypes with the clinical phenotypes. Methods A total of 44 HbH disease patients were enrolled in this study. They were clinically and haematologically assessed. The patients were tested for 21 common α-globin gene mutations using multiplex PCR and reverse hybridization. According to the genotype, the patients were categorized into two separate sub-groups, deletion and non-deletion types HbH disease. Results Within the studied HbH disease patients, eight different α-globin gene mutations were detected in nine different genetic arrangements. The --MED and -α3.7 deletions were the two most frequently encountered mutations (37.5 and 35.2% respectively). Patients with deletion genotypes constituted 70.4%. The most common detected genotype was --MED/−α3.7 (59.1%), followed by αpoly-A1α/αpoly-A1α (13.6%). For the first time, coinheritance of two relatively mild mutations (−α3.7/ααAdana) was unpredictably detected in a 1.5 year-old child with Hb of 7.1 g/dL. Conclusion The HbH disease patients’ clinical characteristics were variable with no ample difference between the deletion and non-deletion types. These results can be of benefit for the screening and management of thalassaemia in this region.


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