Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “G6PD”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 307 records · Page 17Linked to original sources
PubMed1984

A unique electrophoretic slow-moving glucose 6-phosphate dehydrogenase variant (G6PD Asahikawa) with a markedly acidic pH optimum.

A new glucose 6-phosphate dehydrogenase (G6PD) variant associated with chronic nonspherocytic hemolytic anemia was discovered in Japan. The patient showed hemolytic crises after upper respiratory infections. The enzyme activity was about 3.8% of the normal. The partially purified enzyme revealed slow anodal electrophoretic mobility, high Km NADP, marked thermal-instability, and increased affinity for a substrate analogue (deamino-NADP). A particular characteristic of this enzyme was a biphasic pH curve with a greatly increased activity at low pH values. From these results, this variant was clearly different from hitherto observed G6PD variants, and was designated G6PD Asahikawa.

Anemia, Hemolytic↗
PubMed1978

G6PD Vientiane: a new glucose-6-phosphate dehydrogenase variant with increased stability.

A new G6PD variant, called G6PD Vientiane, has been discovered in a patient from Laos. The characteristics of this variant are: mild enzyme deficiency (about 50% of the normal activity) in the granulocytes and the red cells, with normal G6PD-related antigen concentration; increased stability; normal Km glucose 6-phosphate and NADP+; increased inhibition constant by NADPH; decreased inhibition by ATP; slightly increased utilization of the substrate analogue; abnormal pH curve, with maximum activity at pH 9.5; slightly reduced starch gel electrophoretic migration. The implications of the molecular stability of a deficient mutant variant are discussed.

Adult↗
PubMed1992

X-linked glucose-6-phosphate dehydrogenase (G6PD) and autosomal 6-phosphogluconate dehydrogenase (6PGD) polymorphisms in baboons.

Electrophoretic polymorphisms of glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) were examined in captive colonies of five subspecies of baboons (Papio hamadryas). Phenotype frequencies and family data verified the X-linked inheritance of the G6PD polymorphism. Insufficient family data were available to confirm autosomal inheritance of the 6PGD polymorphism, but the electrophoretic patterns of variant types (putative heterozygotes) suggested the codominant expression of alleles at an autosomal locus. Implications of the G6PD polymorphism are discussed with regard to its utility as a marker system for research on X-chromosome inactivation during baboon development and for studies of clonal cell proliferation and/or cell selection during the development of atherosclerotic lesions in the baboon model.

Alleles↗
PubMed2001

A new glucose-6-phosphate dehydrogenase variant G6PD Sugao (826C-->T) exhibiting chronic hemolytic anemia with episodes of hemolytic crisis immediately after birth.

A case of glucose-6-phosphate dehydrogenase (G6PD) deficiency associated with chronic hemolysis with episodes of hemolytic crisis immediately after birth is reported. The propositus was a 1-month-old Japanese male infant. Molecular analysis of the G6PD gene revealed a novel missense mutation (826C-->4T) in exon 8 predicting a single amino acid substitution, Pro276Ser. The mother was confirmed to be heterozygous for this mutation. We designated this novel class 1 variant as G6PD Sugao. Pro276 is a phylogenetically conserved residue that may play a significant role in dimer formation.

Anemia, Hemolytic, Congenital↗
PubMed1984

Cross-reacting material to monoclonal anti-G6PD in the absence of catalytic activity.

Monoclonal antibody prepared against highly purified rat liver G6PD was used to probe the mode of regulation of this enzyme in a mammalian model system. Material cross-reacting with antibody against liver G6PD was found in similar amounts in extracts of two genetically related rat hepatoma cell lines, only one of which exhibits detectable enzymatic activity when both are cultured under identical conditions in vitro. The data suggest a post-translational event is necessary for the expression of catalytic activity for G6PD in this model system.

Animals↗
PubMed1989

Deleterious synergistic effects of ascorbate and copper on the development of Plasmodium falciparum: an in vitro study in normal and in G6PD-deficient erythrocytes.

The effects of ascorbate and copper on the development of Plasmodium falciparum were studied in two modes: pretreatment of uninfected erythrocytes followed by infection by P. falciparum and treatment of parasitized erythrocytes. Pretreatment of G6PD(+) cells with ascorbate caused a slight enhancement in parasite development, while in G6PD(-) cells a suppressive effect on the plasmodia was demonstrated. Copper alone interfered with parasite growth in both cell types. The combination of copper and ascorbate arrested parasite maturation, an effect which was more pronounced in G6PD(-) cells. Synergism between copper and ascorbate was better demonstrated following the treatment of infected erythrocytes: while ascorbate alone supported parasite development and copper alone had only a marginal suppressive effect, the combination of copper and ascorbate yielded a marked inhibition of parasite growth. Ascorbate proved destructive to the parasites in the presence of adventitious copper, or on the second day of the parasite life cycle. In these cases it acted as a pro-oxidant, while in other systems, in particular in the presence of a chelator, ascorbate acted as an antioxidant and promoted parasite growth. The understanding of the role of transition metals and free radicals in parasite development and injury could shed light on novel approaches to fight malaria.

Animals↗
PubMed2004

Glucose 6 phosphate dehydrogenase (G6PD) deficiency is a possible risk factor for the development of preeclampsia.

Preeclampsia is partially attributed to lipid peroxidation of the syncytitrophoblast plasma membranes (SPMs). Peroxidation of the SPMs could be augmented when the capacity of the cells to produce antioxidant molecules is diminished. One of the most important antioxidant molecules that protects the SPMs is the reduced glutathione (GSH). The latter is produced in the pentose phosphate pathway that requires normal activity of glucose 6 phosphate dehydrogenase (G6PD). Therefore, it is hypothesized that pregnant women with G6PD deficiency are at higher risk for development of preeclampsia than those with normal G6PD activity. Deficiency of this enzyme leads to the deficiency of reduced GSH which is required to protect SPMs against lipid peroxidation and the consequent obstetric morbidity.

Comorbidity↗
PubMed2003

New World monkey phylogeny based on X-linked G6PD DNA sequences.

The Platyrrhini, or New World monkeys, are an infraorder of Primates comprised of 16 genera. Molecular phylogenetic analyses have consistently sorted these genera into three groups: the Pitheciidae (e.g., saki and titi monkeys), Atelidae (e.g., spider and howler monkeys), and Cebidae (e.g., night monkeys, squirrel monkeys, and tamarins). No consensus has emerged on the relationships among the three groups or within the Cebidae. Here, approximately 0.8 kb of newly generated intronic DNA sequence data from the X-linked glucose-6-phosphate dehydrogenase (G6PD) locus have been collected from nine New World monkey taxa to examine these relationships. These data are added to 1.3 kb of previously generated G6PD intronic DNA sequence data [Mol. Phylogenet. Evol. 11 (1999) 459]. Using distance and parsimony-based techniques, G6PD sequences provide support for an initial bifurcation between the Pitheciidae and the remaining platyrrhines, linking Atelidae and Cebidae as sister taxa. Bayesian methods provided a conflicting phylogeny with Atelidae as outgroup. Within the Cebidae, a sister relation between Aotus and the Cebus/Saimiri clade is favored by parsimony analysis, but not by other analyses. Potential reasons for the difficulty in resolving family level New World monkey phylogenetics are discussed.

Animals↗
PubMedDate not supplied

Molecular characterization of G6PD Insuli--a novel 989 CGC --> CAC (330 Arg --> His) mutation in the Indian population.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is the most common red cell enzymopathy among humans. G6PD deficiency was reported in India more than 30 years ago and about 13 biochemically characterized variants have been reported. We now describe the molecular characterization of a distinct biochemical variant from India which was previously characterized by us as a unique Class IV variant with fast electrophoretic mobility. The sequence of the G6PD gene from this variant has revealed the presence of a novel 989 G --> A mutation in exon 9 with a predicted amino acid change of Arg330His.

Adolescent↗
PubMed1996

Henna (Lawsonia inermis Linn.) inducing haemolysis among G6PD-deficient newborns. A new clinical observation.

Over a 10-year period, 15 glucose-6-phosphate dehydrogenase (G6PD)-deficient male newborns were admitted to Al-Jahra Hospital with acute haemolysis a few days after applying henna dye over the body, which is a unique Bedouin tribal practice to celebrate the arrival of the first-born boy. Laboratory investigations revealed significant anaemia, reticulocytosis and indirect hyperbilirubinaemia among the index newborns as compared with controls (p < 0.001). The mean (SD) haemoglobin concentration in index patients was 113.4 (13.4) g/l vs 171.2 (11.2) g/l in controls, reticulocytic count 13.8% (4.2%) vs 1.4% (0.74%), and indirect bilirubin 382.8 (58.7) mumol/l vs 63.7 (61.4) mumol/l. G6PD-deficient newborns with haemolysis linked to henna application had delayed age at presentation and a higher reticulocytic count and hyperbilirubinaemia compared with non-henna-induced haemolysis (p < 0.05). Percutaneous henna absorption is well recognized and clinical findings support the harmful effect of henna on G6PD-deficient red blood cells. A local health education programme has been established to prevent the use of henna dye in infancy.

Administration, Topical↗
PubMed1990

Comparison of in vitro and in vivo activities associated with the G6PD allozyme polymorphism in Drosophila melanogaster.

Earlier studies of the A and B allozymes at the G6pd locus show a differential ability of the genotypes to suppress the loss of viability associated with a low activity 6-phosphogluconate dehydrogenase mutation, 6Pgdlo1. This observation indicates a relatively lower activity for the A allozyme genotype, but it is not known if this level of suppression required a large difference in in vivo activity. To clarify this difference an analysis of the biochemical properties of the purified allozymes was carried out, as well as an analysis of the activity level associated with an original low activity P element-derived allele which had partially reverted and lost its suppression ability. G6PD activity and protein level were studied in 47 X chromosome lines from North America. The A genotype averages a 9% lower Vmax. From analysis of the correlation between G6PD activity and protein level it remains unclear whether the allozyme Vmax difference results from dissimilarity in protein level or kcat. At 25 degrees and physiological pH, comparative studies of the steady-state kinetics show the two purified allozyme variants differ significantly in their KM values for glucose-6-phosphate and NADP, and the K1 for NADPH. In aggregate these parameters predict the A genotype possesses a 20% lower in vitro catalytic efficiency. A partial revertant of a P element-derived low activity B variant, was shown to lose the ability to suppress 6Pgdlo1 low viability after acquiring only 60% of normal B activity. This last comparison shows the A genotype activity must be reduced in vivo by at least 40%.

Analysis of Variance↗
PubMed1992

Direct measurement of in vivo flux differences between electrophoretic variants of G6PD from Drosophila melanogaster.

Demonstrating that naturally occurring enzyme polymorphisms significantly impact metabolic pathway flux is a fundamental step in examining the possible adaptive significance of such polymorphisms. In earlier studies of the glucose-6-phosphate dehydrogenase (G6PD) polymorphism in Drosophila melanogaster, we used two different methods, exploiting both genotype-dependent interactions with the 6Pgd locus, and conventional steady-state kinetics to examine activity differences between the two common allozymes. In this report we use 1-14C- and 6-14C-labeled glucose to estimate directly genotype-dependent flux differences through the pentose shunt. Our results show that G6pdA genotype possesses statistically lower pentose shunt flux than G6pdB at 25 degrees. We estimate this to be about a 32% reduction, which is consistent with the two former studies. These results reflect a significant responsiveness of pentose shunt flux to activity variation at the G6PD-catalyzed step, and predict that the G6PD allozymes generate a polymorphism for pentose shunt flux.

Animals↗
PubMed1996

Amino acid polymorphism and rare electrophoretic variants of G6PD from natural populations of Drosophila melanogaster.

Identifying the amino acid changes responsible for electrophoretic variants is essential to understanding the significance of allozyme polymorphism in adaptation. The amino acid mutations responsible for the common G6PD allozyme polymorphisms in Drosophila melanogaster have been recently described. This study characterizes the amino acid changes associated with 11 rare electrophoretic G6PD variants. The 11 rare electrophoretic variants result from six independent amino acid mutations. The in vivo function of the rare variants was determined in an earlier study and most variants fell into one of two function classes. It is shown here that the function of the rare variants reflects the state of the Pro/Leu mutation responsible for the A/B allozyme polymorphism in each variant. Two mutations destabilize quaternary structure resulting in shifts from tetrameric dimeric alleles, and one of these also results in a variant with in vivo function intermediate to A and B. That mutation is an aspartic-acid-to-asparagine change that is two residues away from the Pro/Leu polymorphism responsible for the A/B dimertetramer quaternary shift. Structure-function relationships based on studies of human G6PD deficiency-associated mutations predict that these last two amino acid changes fall within the protein domain responsible for NADP binding.

Amino Acid Sequence↗
PubMed1998

Sickle cell disease in Bahrain: coexistence and interaction with glucose-6-phosphate dehydrogenase (G6PD) deficiency.

The object was to determine the frequency of glucose-6-phosphate dehydrogenase in Bahraini individuals with HbS as compared to those without HbS. Haemolysates of erythrocytes from 310 Bahraini individuals attending Health Centres were obtained, electrophoresed on cellulose acetate at PH 8.2-8.6, and stained for G6PD. HbS was present in 125 individuals (study group) and in 185 only HbA was present (control group). G6PD deficiency (very low to undetectable) was identified in 59 samples (47 per cent) of the study group and 35 (19 per cent) of the control group. A positive correlation between G6PD deficiency and HbS is present in Bahraini individuals tested. This is similar to the situation in the Eastern Province of Saudi Arabia. We speculate that the observation could be explained on the basis of historic endemicity of Falciparum malaria in both regions on the East coast of the Saudi Peninsula.

Adolescent↗
PubMed1995

Hemolytic jaundice due to G6PD deficiency causing kernicterus in a female newborn.

Glucose-6-phosphate dehydrogenase (G6PD) deficiency is an inherited deficiency of an enzyme necessary to protect the erythrocyte from oxidative stress and hemolysis. Without this enzyme, affected neonates are at risk for acute onset of hemolytic jaundice and severe sequelae, from hearing loss and mild retardation to kernicterus. In some populations, especially in blacks and those of Mediterranean ancestry, the incidence of G6PD deficiency has been reported to be as high as 10% to 14%. We describe a female newborn who had acute onset of hyperbilirubinemia leading to kernicterus in the first week of life. Investigation proved G6PD deficiency. This case suggests a need to screen for this disease or to follow serial bilirubin levels in populations at risk.

Anemia, Hemolytic↗
PubMed1999

Maternal inheritance of manic depression in hemizygotes for the G6PD-Mediterranean mutation. Indirect evidence for Xq28 transmission in Sardinia.

Both X-linkage and a parent-of-origin effect have been hypothesized in manic-depressive disorder. We have previously shown an allelic association between X-linked G6PD deficiency and manic depression in Mediterranean populations. To test both X-linkage and a parent-of-origin effect in manic depression further, we have studied 274 Sardinian manic-depressive probands and their parents. Excess of maternal transmission (P = 0.005) of major affective disorder was found in male probands carrying the G6PD-Mediterranean mutation. Our results provide indirect molecular support for an association between manic depression and the Xq28 chromosome region in Sardinia. Further studies on Xq28 using tests of allelic association and transmission disequilibrium with multiple DNA markers are required, to clarify the nature of the association we have found. Our study cannot implicate or exclude a direct role for G6PD deficiency in the aetiology of manic depression.

Adult↗
PubMed1994

Molecular characterisation of an Italian G6PD variant responsible for chronic non-spherocytic haemolytic anaemia.

An Italian deficient G6PD variant associated with chronic non-spherocytic haemolytic anaemia (CNSHA) was biochemically characterised and studied at molecular level. Single-strand conformation polymorphism (SSCP) analysis led to the identification of an abnormal migration pattern of an amplified fragment encompassing exons 10 and 11 of the G6PD gene. Sequence analysis of both strands using an automated fluorescent DNA sequencer revealed a G-->A transition at nt. position 1246 in exon 10. A C-->T substitution at nt. 1311 in exon 11 was also found, which has already been described as a silent mutation common in Caucasians. The 1246 G-->A mutation has been described only in a Japanese subject with CNSHA (G6PD Tokyo) not associated with the 1311T polymorphism, suggesting that this mutation may have arisen independently in Europe and Asia.

Adult↗
PubMed1980

The HLA system and G6PD deficiency in the Bulgarian population.

HLA typing was done on 2,956 healthy, unrelated individuals living in four areas in Bulgaria. Of these, 163 had G6PD deficiency. The persons examined lived in villages situated at different altitudes. A low degree of correlation was found only for HLA-A1, -Aw23, -Bw35 and -B40 in the selected group with G6PD deficiency. The decrease of phenotype frequency of each HLA antigen was found to be directly proportional to the decrease of G6PD deficiency frequencies and related to environmental altitude, which is very typical for this selected group of carriers of this deficiency.

Bulgaria↗