Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0039730 (thalassemia)
 10,305 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Glutathione reductase (GR) deficiency is reported to occur with a variable frequency in some populations of the world. In this study, the populations of two regions of Saudi Arabia which have a high frequency of sickle cell, thalassaemia and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency, were screened for GR deficiency. Studies were also carried out to investigate the frequency of GR deficiency with other genetic blood disorders. The frequencies of complete GR deficiency were 0.0065 and 0.006, while those of partial deficiency were 0.146 and 0.074 in Al-Hafouf and Khaiber, respectively. GR deficiency was encountered in combination with the sickle gene, the G-6-PD deficiency gene and the thalassaemia gene in both regions. Individuals with GR deficiency showed slightly reduced haematological parameters. In thalassaemic/GR-deficient subjects, mean cell volume and mean cell haemoglobin were low, while in sickle cell anaemia patients with GR deficiency the haematological parameters were higher than in sickle cell anaemia patients without GR deficiency.
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PMID:Glutathione reductase deficiency in association with sickle cell and thalassaemia genes in Saudi populations. 404 83

Admission screening was performed on 684 Chinese-Canadian patients for thalassemia, abnormal hemoglobins and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Thirty-six healthy Chinese adults were also studied. The incidence of beta-thalassemia minor (hemoglobin A(2) greater than 3.5%) was 3.8%. Presumptive alpha-thalassemia minor (demonstration of occasional red cells containing hemoglobin H inclusion bodies) was found in 6.7%. Two patients had findings consistent with alpha-beta-thalassemia. The incidence of G-6-PD deficiency (abnormal methemoglobin reduction test) in adult males was 4.7%. In a parallel study the incidence of hemoglobin Bart's in 310 Chinese newborns was 6.8%. Two mutant hemoglobins were found - hemoglobin E and hemoglobin J (Bangkok).
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PMID:Thalassemia and G-6-PD deficiency in Chinese-Canadians: admission screening of a hospital population. 556 48

Certain aspects of the metabolism of centrifuged young and old erythrocytes in hemoglobin H disease have been examined and compared with similar studies of beta thalassemia and normal cells. Glycolysis, hexose monophosphate shunt activity (HMPS), potassium flux, and glutathione (GSH) content were measured. The distributions of hemoglobins H and F, as well as the activities of erythrocyte glucose-6-phosphate dehydrogenase (G6PD) and glutamic oxalacetic transaminase (GOT), were utilized for estimations of the relative ages of the cell samples. The young erythrocytes in hemoglobin H disease differed in several respects from older hemoglobin H cells. They contained more soluble hemoglobin H and GSH and, after splenectomy, fewer inclusions. HMPS activity was subnormal in hemoglobin H young cells and rose to normal activity in old cells. Potassium flux tended to increase in old cells when inclusions were present.Beta thalassemia young cells contained less hemoglobin F and, after splenectomy, more inclusions than old cells. In addition, they had markedly increased glycolysis and HMPS activity. GSH was randomly distributed. Potassium flux was increased in younger cells and particularly increased when inclusions appeared in younger cells after splenectomy. The results are interpreted to indicate that inclusion formation is associated with increased erythrocyte cation permeability in the thalassemia syndromes. This is not related to the level of intracellular GSH. The decreased HMPS activity in young hemoglobin H cells may be due to the presence of the extra thiols of soluble hemoglobin H which can act as a reducing agent. The substitution of hemoglobin H for glutathione in this capacity would then spare the NADPH-requiring glutathione reductase system. As a consequence, HMPS activity would decline. However, in older cells the oxidized hemoglobin H precipitates; these must rely upon GSH and glutathione reductase activity for thiol reduction capacity. Accordingly, HMPS activity increases to normal in the old cell population.
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PMID:Influence of hemoglobin precipitation on erythrocyte metabolism in alpha and beta thalassemia. 576 25

In this study, we carried out restriction endonuclease mapping in order to characterize the alpha-globin genotype of 10 Sardinian beta 0-thalassemia heterozygotes, all of whom presented with normal red blood cell indices and increased HbA2 levels. In 8 of these subjects, we found the deletion of two alpha-globin genes (-alpha/-alpha), and in the remaining two the deletion of a single alpha-globin gene (-alpha/alpha alpha). In three of these carriers with the (-alpha/-alpha) alpha-globin genotype and in one with the (-alpha/alpha alpha) genotype, we also found the glucose-6-phosphate dehydrogenase (G6PD) defect of the Mediterranean type. On the basis of these findings, we may conclude that the interaction of heterozygous beta 0-thalassemia with alpha-thalassemia, due to the deletion of either one or two alpha-globin genes, may lead to the production of red blood cells with normal indices. The association of the G6PD defect with this thalassemia gene complex may eventually contribute to this effect. We suggest, therefore, that screening programs for heterozygous beta-thalassemia in populations where alpha-thalassemia is also prevalent, should incorporate the determination of HbA2 in the first set of tests.
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PMID:Phenotypic effect of heterozygous alpha and beta 0-thalassemia interaction. 630 42

It is suggested here that a Hemoglobin S (HbS)-mediated membrane oxidant injury is responsible for both the protection from malaria infection in the heterozygous sickle cell state, and for a critical pathologic process in homozygous sickle cell disease. This suggestion is arrived at by applying to the HbS condition the oxidant stress model for malaria resistance. Such a model had been developed to explain the protection from malaria in thalassemia and in glucose-6-phosphate dehydrogenase (G6PD) deficiency (9).
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PMID:Hemoglobin S-mediated membrane oxidant injury: protection from malaria and pathology in sickle cell disease. 647 60

Genetic markers have recently been found to be much more polymorphic than expected. Such extensive human polymorphisms may be partly explained by a number of genetic and environmental factors, including infectious diseases. Malaria, which was very widespread in the past and still poses a problem in many countries today, is a good candidate for research. The association between malaria and glucose-6-phosphate dehydrogenase (G6PD) deficiency is well-known, but more should be done to determine the mechanisms responsible for this positive correlation and to confirm that malaria is a strong selective factor for many other genotypes also. The present paper refers to a WHO project on genetic markers and susceptibility to infectious diseases, which is concerned mainly with G6PD deficiency and the following genetic markers: haemoglobinopathies, including the beta-thalassaemia trait and ABO, Rh, MN, Duffy, secretory types (Ss), and human leukocyte antigens (HLA). Since malaria was eradicated in Bulgaria many years ago, human populations from this country, living at different altitudes above sea-level, were used as a model for analysis of the malaria hypothesis. The data for G6PD deficiency confirm that malaria was a selective factor in lowland areas where malaria infection was more frequent in the past. It is, moreover, apparent that in addition to malaria some other factors also play a selective role.
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PMID:Frequency of glucose-6-phosphate dehydrogenase deficiency in relation to altitude: a malaria hypothesis. 696 37

The study reports results of investigations on hemoglobin, pseudocholinesterase, Australia antigen and glucose-6-phosphate dehydrogenase in 153 mental retardates and 161 controls. beta-thalassemia and the hemoglobin phenotype AS occurred more in patients. At the pseudocholinesterase locus, the patients had significantly higher frequencies of E1a and E1f (p less than 0.001). Mental retardation was found to be associated also with presence of Australia antigen and with G-6-PD deficiency. A model to explain these findings has been proposed.
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PMID:Biochemical genetics and mental retardation: a study of hemoglobins, Australia antigen and the enzymes pseudocholinesterase and glucose-6-phosphate dehydrogenase. 727 94

Haemoglobin variants, beta-thalassaemia and glucose-6-phosphate dehydrogenase (G-6-PD) types were studied in 702 individuals from Buchanan, Liberia. In this population haemoglobins S and C, beta-thalassaemia and G-6-PD deficiency were found together. There was a considerable tribal variation. In the tribes of eastern Liberia the S- and C-genes were uncommon and the beta-thalassaemia gene was rather frequent, while in western Liberia the S- and C-genes were more frequent and beta-thalassaemia uncommon. In the central and northern parts the S- and beta-thalassaemia genes were found together in relatively high frequencies. The rate of malaria infection was found to be lower in individuals with the sickle cell and beta-thalassaemia traits than in individuals with haemoglobin AA, but the difference was not statistically significant. The frequency of the delta-chain gene B2 was 1.4% in the total material and there was no significant tribal variation for this gene. The frequency of G-6-PD deficiency estimated in males was 16%.
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PMID:Haemoglobin variants, beta-thalassaemia and G-6-PD types in Liberia. 733 23

In Saudi Arabia two major forms of sickle cell anaemia (SCA) have been identified, a benign SCA is reported mainly in the Eastern province and a severe form is reported in other parts of the country. Multiple factors including associated alpha-thalassaemia, elevated Hb F and glucose-6-phosphate dehydrogenase (G-6PD) deficiency have often been reported as modifying the clinical presentation of the disease. However, these factors do not completely explain the amelioration in the clinical manifestations in SCA. More recently interest has been directed toward the investigations of the regions surrounding the beta-globin genes. Using restriction endonucleases extensive polymorphism has been identified and different haplotypes have been encountered. We initiated studies in the different regions of Saudi Arabia. Our studies on the Saudi population from different regions of the country using Hinc II and Hind III showed that the beta-globin gene haplotype ++-++ is associated with a mild sickle cell anaemia, while ----+ is associated with the severe form of the disease. Xmn I polymorphic site 5' to the G gamma gene and 7.6 kb Hpa I fragments 3' to the beta-globin gene are also associated mainly with the mild disease. This paper presents and compares the two major forms of SCA in Saudi population and relates it to the genetic heterogeneity.
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PMID:The relationship of the genetic heterogeneity of sickle cell gene to clinical manifestations. 809 5

In order to develop a rational and early detection of combined forms of hemoglobin and enzymopathies, 1500 samples of neonatal cord blood were tested for alpha- and beta-thalassemia, of abnormal hemoglobins S and C, of methemoglobinemia and for hereditary persistence of fetal hemoglobin as well as 428 samples were examined for glucose-6-phosphate dehydrogenase (EC 1.1.1.49) and glutathione reductase (EC 1.6.4.2) deficiencies. For this purpose, isoelectrofocusing in Multiphor-2117 polyacrylamide-ampholine plates (LKB, Sweden) at pN 3.5-9.5 and pH 5.5-8.5 was carried out with subsequent laser densitometry of gels (Densitometer 2202, LKB). The data obtained were analyzed simultaneously in biochemical, hematological and genealogical studies. Hereditary impairments detected were evidenced by genealogical analysis.
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PMID:[Detection of combined forms of hemoglobino- and enzymopathies in newborns]. 830 76


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