scholarly journals The molecular basis of alpha thalassemia in India. Its interaction with the sickle cell gene

Blood ◽  
1988 ◽  
Vol 71 (2) ◽  
pp. 467-472 ◽  
Author(s):  
AE Kulozik ◽  
BC Kar ◽  
GR Serjeant ◽  
BE Serjeant ◽  
DJ Weatherall

Abstract The alpha globin genotype of a total of 282 Indians from Orissa state has been analyzed. The overall alpha thalassemia gene frequency is 0.29, most frequently caused by the -alpha 3.7 and -alpha 4.2 deletions. In one family a novel -alpha 3.5 deletion removing the alpha 1 globin gene with some of its flanking sequences has been found, suggesting further sequence homology of the alpha globin gene cluster 3′ to the alpha 1 globin gene. Patients with sickle cell disease and alpha thalassemia had higher hemoglobin (Hb) levels, RBC counts, and Hb A2 levels, and lower reticulocyte counts, MCV, MCH, and Hb F levels than those with a normal alpha genotype. The frequency of splenomegaly was not influenced by the alpha globin genotype. A higher prevalence of alpha thalassemia was found in patients greater than or equal to 10 years of age than in the younger group, suggesting a possible advantageous effect of alpha thalassemia on the survival of patients with sickle cell disease.

Blood ◽  
1988 ◽  
Vol 71 (2) ◽  
pp. 467-472
Author(s):  
AE Kulozik ◽  
BC Kar ◽  
GR Serjeant ◽  
BE Serjeant ◽  
DJ Weatherall

The alpha globin genotype of a total of 282 Indians from Orissa state has been analyzed. The overall alpha thalassemia gene frequency is 0.29, most frequently caused by the -alpha 3.7 and -alpha 4.2 deletions. In one family a novel -alpha 3.5 deletion removing the alpha 1 globin gene with some of its flanking sequences has been found, suggesting further sequence homology of the alpha globin gene cluster 3′ to the alpha 1 globin gene. Patients with sickle cell disease and alpha thalassemia had higher hemoglobin (Hb) levels, RBC counts, and Hb A2 levels, and lower reticulocyte counts, MCV, MCH, and Hb F levels than those with a normal alpha genotype. The frequency of splenomegaly was not influenced by the alpha globin genotype. A higher prevalence of alpha thalassemia was found in patients greater than or equal to 10 years of age than in the younger group, suggesting a possible advantageous effect of alpha thalassemia on the survival of patients with sickle cell disease.


1999 ◽  
Vol 5 (6) ◽  
pp. 1254-1258
Author(s):  
M. A. El Hazmi ◽  
A. S. Warsy ◽  
N. Bashir ◽  
A. Beshlawi ◽  
I. R. Hussain

Wecollaborated with researchers from Egypt, Syrian Arab Republic and Jordan in a study of patients with sickle-cell disease from those countries, and from various parts of Saudi Arabia, in order to investigate the influence of genetics on the clinical presentation of the disease, and to attempt to determine the origin of the sickle-cell gene in Arabs. Our results suggest that beta-globin gene haplotypes influence the clinical presentation of sickle-cell disease, and that there are at least two major foci for the origin of the sickle-cell gene, one in the eastern part of Saudi Arabia, and the other in the populations of North Africa and the north-western part of the Arabian peninsula


2022 ◽  
Vol 14 (1) ◽  
pp. e2022001
Author(s):  
FASOLA ATINUKE

Background: Sickle cell disease is a protean disease with limited data on the phenotypic and genetic variants in Nigeria. This study was conducted to provide baseline data on these variants by characterizing the existing forms of sickle cell disease and correlating these with basic hematological parameters. Methods: Adult and pediatric patients with SCD were recruited from a tertiary health centre in Nigeria. Patients were age and sex matched with healthy controls. Blood samples were obtained for Full Blood Count, phenotyping by High Performance Liquid Chromatography and genotyping for alpha thalassemia by multiplex gap polymerase chain reaction. Data analysis was done using IBM SPSS statistics version 23. Results: A total of 130 patients with sickle cell disease and 117 controls were studied. Alpha thalassemia in the study population was due to a 3.7kb deletion in the alpha globin gene cluster at a prevalence of 45.4% in the patients and 47% in controls. The prevalence of the various existing forms of SCD genotype was: Homozygous S without alpha gene deletion (HbSS)- 39.2%; HbSC - 10.8%; HbSα+1- 35.4%; HbSα+2 - 6.9% and HbSF- 7.7%. HbA2 was significantly elevated in individuals with two alpha gene deletions (HbSα+2). HbF and HbA2 were negatively correlated with each other (r= -0.587, p < 0.001). Individuals with the HbSC genotype followed by HbSα+2 had the best hematological parameters. Conclusions: Hematological parameters varied with hemoglobin genotype. The C hemoglobin and homozygous alpha thalassemia deletion had better ameliorating effect on SCD hematological parameters than the F hemoglobin in this population.  


2011 ◽  
Vol 412 (13-14) ◽  
pp. 1257-1261 ◽  
Author(s):  
Philippe Joly ◽  
Philippe Lacan ◽  
Caroline Garcia ◽  
Angelique Delasaux ◽  
Alain Francina

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Huiqiao Chen ◽  
Zixuan Wang ◽  
Shanhe Yu ◽  
Xiao Han ◽  
Yun Deng ◽  
...  

AbstractThe human ζ-globin gene (HBZ) is transcribed in primitive erythroid cells only during the embryonic stages of development. Reactivation of this embryonic globin synthesis would likely alleviate symptoms both in α-thalassemia and sickle-cell disease. However, the molecular mechanisms controlling ζ-globin expression have remained largely undefined. Moreover, the pharmacologic agent capable of inducing ζ-globin production is currently unavailable. Here, we show that TRIAC, a bioactive thyroid hormone metabolite, significantly induced ζ-globin gene expression during zebrafish embryogenesis. The induction of ζ-globin expression by TRIAC was also observed in human K562 erythroleukemia cell line and primary erythroid cells. Thyroid hormone receptor α (THRA) deficiency abolished the ζ-globin-inducing effect of TRIAC. Furthermore, THRA could directly bind to the distal enhancer regulatory element to regulate ζ-globin expression. Our study provides the first evidence that TRIAC acts as a potent inducer of ζ-globin expression, which might serve as a new potential therapeutic option for patients with severe α-thalassemia or sickle-cell disease.


Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 296
Author(s):  
Rosa Vona ◽  
Nadia Maria Sposi ◽  
Lorenza Mattia ◽  
Lucrezia Gambardella ◽  
Elisabetta Straface ◽  
...  

Sickle cell disease (SCD) is the most common hereditary disorder of hemoglobin (Hb), which affects approximately a million people worldwide. It is characterized by a single nucleotide substitution in the β-globin gene, leading to the production of abnormal sickle hemoglobin (HbS) with multi-system consequences. HbS polymerization is the primary event in SCD. Repeated polymerization and depolymerization of Hb causes oxidative stress that plays a key role in the pathophysiology of hemolysis, vessel occlusion and the following organ damage in sickle cell patients. For this reason, reactive oxidizing species and the (end)-products of their oxidative reactions have been proposed as markers of both tissue pro-oxidant status and disease severity. Although more studies are needed to clarify their role, antioxidant agents have been shown to be effective in reducing pathological consequences of the disease by preventing oxidative damage in SCD, i.e., by decreasing the oxidant formation or repairing the induced damage. An improved understanding of oxidative stress will lead to targeted antioxidant therapies that should prevent or delay the development of organ complications in this patient population.


2004 ◽  
Vol 286 (4) ◽  
pp. L705-L714 ◽  
Author(s):  
Kirkwood A. Pritchard ◽  
Jingsong Ou ◽  
Zhijun Ou ◽  
Yang Shi ◽  
James P. Franciosi ◽  
...  

Vaso-occlusive events are the major source of morbidity and mortality in sickle cell disease (SCD); however, the pathogenic mechanisms driving these events remain unclear. Using hypoxia to induce pulmonary injury, we investigated mechanisms by which sickle hemoglobin increases susceptibility to lung injury in a murine model of SCD, where mice either exclusively express the human α/sickle β-globin (hαβS) transgene (SCD mice) or are heterozygous for the normal murine β-globin gene and express the hαβStransgene (mβ+/-, hαβS+/-; heterozygote SCD mice). Under normoxia, lungs from the SCD mice contained higher levels of xanthine oxidase (XO), nitrotyrosine, and cGMP than controls (C57BL/6 mice). Hypoxia increased XO and nitrotyrosine and decreased cGMP content in the lungs of all mice. After hypoxia, vascular congestion was increased in lungs with a greater content of XO and nitrotyrosine. Under normoxia, the association of heat shock protein 90 (HSP90) with endothelial nitric oxide synthase (eNOS) in lungs of SCD and heterozygote SCD mice was decreased compared with the levels of association in lungs of controls. Hypoxia further decreased association of HSP90 with eNOS in lungs of SCD and heterozygote SCD mice, but not in the control lungs. Pretreatment of rat pulmonary microvascular endothelial cells in vitro with xanthine/XO decreased A-23187-stimulated nitrite + nitrate production and HSP90 interactions with eNOS. These data support the hypotheses that hypoxia increases XO release from ischemic tissues and that the local increase in XO-induced oxidative stress can then inhibit HSP90 interactions with eNOS, decreasing ·NO generation and predisposing the lung to vaso-occlusion.


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