Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0002895 (sickle cell disease)
 11,747 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We studied the interactions of the A- variety of glucose-6-phosphate dehydrogenase (G6PD) deficiency and sickle cell anemia (HbSS) to see if G6PD deficiency influenced laboratory and clinical features of HbSS. A total of 801 male patients over age 2 had G6PD electrophoresis on cellulose acetate membranes. Assays of both G6PD activity and hexokinase activity were then done on all samples that had an electrophoretic pattern other than the normal wild type (GdB). The collection of clinical data used a standardized protocol. Using cluster analyses we classified 10.4% males to be G6PD deficient, while 18.4% had the functionally normal GdA+ enzyme. The prevalence of G6PD deficiency did not change significantly when age was stratified by decade, suggesting little survival advantage or disadvantage of the combination of G6PD deficiency and HbSS. Compared to patients who were not G6PD deficient, there were no significant differences in the hemoglobin concentration, mean corpuscular volume, reticulocyte count, bilirubin, or SGOT level in patients with HbSS who had G6PD deficiency. The incidence of painful episodes, sepsis, or acute anemic episodes was similar in both groups. Our results are consistent with recent studies of smaller numbers of patients that have found little influence of G6PD deficiency upon HbSS. Specifically, we found no evidence that G6PD enhanced the severity of hemolysis or increased the incidence of acute anemic episodes or sepsis in HbSS.
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PMID:Effects of glucose-6-phosphate dehydrogenase deficiency upon sickle cell anemia. 334 44

Sickle cell haemoglobin (Hb S) and glucose-6-phosphate dehydrogenase (G-6-PD) deficiency occur at a variable prevalence in different regions of Saudi Arabia. The interaction between the two genes was investigated in 1859 Saudi males in different regions where the two genes were known to exist at both a high and a low frequency. The frequency of G-6-PD deficiency was the highest in the sickle cell anaemia (SS) cases. Furthermore, in all areas except Tehamat-Aseer (on the Red Sea), the frequency of G-6-PD deficiency was greater in the sickle cell heterozygotes (AS) than in the normal (AA) individuals. The interaction between G-6-PD deficiency and sickle cell gene in the homozygotes and heterozygotes may provide additional benefit against environmental and genetical factors, and may play a role in the amelioration of sickle cell disease in Saudis.
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PMID:Interaction between glucose-6-phosphate dehydrogenase deficiency and sickle cell gene in Saudi Arabia. 347 17

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

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

The red cells' antioxidant defense mechanisms were compared between individuals with sickle cell disease and those with hemolytic anemia and reticulocytosis. In sickle cell disease, there was a significant increase in incubated Heinz body formation (p less than .001), a decrease in reduced glutathione concentration (p less than .01), an increase in glucose-6-phosphate dehydrogenase activity (p less than .01), and a decrease in glutathione reductase activity (p less than .005). The patients with sickle cell disease hd an absolute increase in the activity of the pentose shunt in the intact red cell after methylene blue stimulation (p less than .05) and in red cell hemolysates (p less than .0250. Heinz body formation (r = .75) and pentose shunt activity in red cell hemolysates (r = .83) were strongly related to the degree of reticulocytosis. Although there was a correlation between the pentose shunt activity in the stimulated red cell and in red cell hemolysates for the patients with hemolytic anemia (r = .58), stimulated shunt activity did not increase as the hemolysate shunt activity increased for the patients with sickle cell disease. There were very strong relationships between the ATP concentration and the reticulocyte count (r = .80) and the hemolysate pentose shunt activity (r = .77) in sickle cel disease. These data suggest that in spite of an absolute increase in stimulated pentose shunt activity, there Is a relative suppression of stimulated shunt activity in the youngest sickle erythrocytes. This may be related, in part, to the inhibitory effects of high concentrations of ATP on the activity of glucose-6-phosphate dehydrogenase.
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PMID:Impaired pentose phosphate shunt function in sickle cell disease: a potential mechanism for increased Heinz body formation and membrane lipid peroxidation. 688 Nov 34

To study the plasma lipid levels in patients with red cell genetic disorders, we investigated 400 normal individuals, 100 sickle cell disease (SCD) patients, 220 sickle cell heterozygotes (Hb AS), and 100 individuals suffering from glucose-6-phosphate dehydrogenase (G-6-PD) deficiency. Whole blood samples were used for the determination of haematological parameters and red cell indices, and plasma was used for the estimation of plasma lipids using Autoanalyser American Monitor 'Parallel'. Haemoglobin types in the haemolysates were separated by electrophoresis and G-6-PD activity was determined using kits from Boehringer Mannheim GmbH. The results from males and females were analysed separately. In each group cholesterol levels were slightly higher in the male population, while the reverse was true for triglyceride. Sickle cell disease patients had significantly (P < 0.05) lower cholesterol level compared to the normal individuals. In the Hb AS and G-6-PD deficient groups no significant differences were encountered. Multiple regression analysis between cholesterol and haematological parameters showed a statistically significant positive correlation (P < 0.01) between plasma cholesterol and total haemoglobin in each group, particularly in the sickle cell disease patients. The results suggest that increased utilization or decreased production may account for the lower cholesterol level in severely anaemic patients, particularly those with sickle cell anaemia.
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PMID:Red cell genetic disorders and plasma lipids. 756 70

Plasma fructosamine, total proteins and albumin were estimated in a group of 77 sickle cell anaemia and 32 glucose-6-phosphate dehydrogenase (G6PD)-deficient Saudi Arabs and the results compared with those obtained in a group of 30 normal controls. The mean values of fructosamine in the sickle cell anaemia and G6PD-deficient patients were not statistically different from those of the controls. The mean values of the total proteins and albumin were also not significantly different from those of the normal group. It is concluded that fructosamine level is not affected by sickle cell anaemia and G6PD deficiency, and provides a useful tool for monitoring diabetic patients in regions with high prevalence of haemoglobinopathies and G6PD deficiency.
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PMID:Fructosamine in HbS and G6PD-deficient Saudi Arabs in the Eastern Province of Saudi Arabia. 775 39

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

A countrywide prospective study aimed at establishing the prevalence of the haemoglobinopathy genes in the Portuguese population was carried out by screening 15,208 randomly selected blood samples from young males. This male based survey provided the opportunity of assessing simultaneously the prevalence of the red cell enzyme glucose-6-phosphate dehydrogenase (G6PD) deficiency, thus giving a picture of these important hereditary anaemias in Portugal. The results showed a low average frequency of beta thalassaemia (0.45%) and haemoglobin S (0.32%) carriers as well as G6PD deficiency (0.51%). However, these disorders are unevenly distributed throughout the country with a higher prevalence in some areas, mainly in the south. The relationship of this pattern of haemoglobinopathies to the known haplotypes linked to beta thalassaemia and sickle cell disease, relevant historical events, and local selective pressure was investigated. Hb D and Hb J are the commonest other structural variants. The implemented programme for control of these hereditary anaemias is described.
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PMID:Hereditary anaemias in Portugal: epidemiology, public health significance, and control. 847 8

Cord blood samples (1039) collected at King Khalid University Hospital were analysed for abnormal haemoglobins using electrophoresis at alkaline and acid pH, for glucose-6-phosphate dehydrogenase (G-6-PD) deficiency using spectrophotometric method and for G-6-PD phenotypes using electrophoresis and specific staining. Only two samples showed the presence of Hb AS and no case of sickle cell anaemia was identified. The Hb S gene frequency was 0.00096. This was the lowest frequency identified so far in different regions of Saudi Arabia. The frequency of G-6-PD deficiency was calculated separately in the males and females, and was found to be 3.605 per cent in the males and 0.195 per cent in the females. Phenotyping showed the presence of G-6-PD-B+ as the normal enzyme at a frequency of 0.943 in both males and females and G-6-PD-A+ at a frequency of 0.0208 in males and 0.0059 in females. The deficient variant was mainly G-6-PD Mediterranean which occurred at a frequency of 0.0341 and 0.0019 in males and females, respectively. Only one case of G-6-PD-A- was identified in the males giving a frequency of 0.0019. This is the first report of Hb S and G-6-PD deficiency genes in cord blood samples in Riyadh. Comparison of the results in Riyadh with values reported elsewhere showed that Riyadh had the lowest frequency of both Hb S and G-6-PD deficiency gene.
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PMID:Sickle cell and G-6-PD deficiency gene in cord blood samples: experience at King Khalid University Hospital, Riyadh. 914 74


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