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 235 records · Page 13Linked to original sources
PubMed1994

[PCR-single-strand conformation (SSCP), DNA direct sequencing analysis in detecting mutation in exon 2 of g6pd gene].

Hereditary glucose-6-phosphate dehydrogenase (G6PD) in red blood cell was one of the most common genetic diseases in South China. The research data of G6PD gene showed that at least 6 point mutations were responsible for various G6PD variants in Chinese. For developing a rapid, sensitive, and effective method to detect point mutation, we applied single-strand conformation (SSCP) analysis for detection of mutation in exon 2 of G6PD gene of 20 cases of G6PD variants. Four of them were found that mobility shift band in one of two single strands DNA is slower than other individuals. PCR direct sequencing for these 4 samples were given a base substitution (T to D) at nucleotide 95 of cDNA. The results indicated that this technique is very simple, sensitive, and useful over other methods of detecting point mutation. The experimental conditions of PCR-SSCP and features of this mutation were discussed at the same time.

Adult↗
PubMed2006

Attitudes and beliefs of pediatricians and genetic counselors regarding testing and screening for CF and G6PD: implications for policy.

There is wide variability in conditions included in state newborn screening (NBS) panels. The American College of Medical Genetics (ACMG) was commissioned by Health Resources and Services Administration to develop a uniform NBS panel. Based on survey data, the ACMG committee proposed a panel that included cystic fibrosis (CF) and glucose-6-phosphate dehydrogenase deficiency (G6PD), although G6PD was excluded from their final recommendations. We examine the attitudes of pediatricians and genetic counselors concerning screening for these two conditions. Data were collected as part of two different studies. Koopmans and Ross surveyed a random sample of 600 pediatricians from four states based on their NBS panels. Hiraki et al. surveyed genetic counselors who were members of the National Society of Genetic Counselors (NSGC) listserv. For this analysis, we compare the health care professionals' (HCPs') attitudes toward a universal NBS program for CF and G6PD, and how their support is influenced by state policy and personal interest in testing their own children. Two hundred twenty-three pediatricians and 267 genetic counselors provided partial or complete responses. Pediatricians are more likely to support NBS for both CF (84%) and G6PD (58%) than genetic counselors (56%, P < 0.001 and 39%, P < 0.001, respectively). Both pediatricians and genetic counselors' attitudes toward screening correlate with interest in screening their own children (P < 0.001). Interest in CF screening also correlates with state policy (pediatricians, P < 0.001; genetic counselors, P < 0.025). The correlation of professional recommendations with state policies and personal preferences reinforces the need for systematic evidence-based reviews rather than reliance on stakeholder opinions for developing national guidelines.

Attitude of Health Personnel↗
PubMed2004

Low membrane protein sulfhydrils but not G6PD deficiency predict ribavirin-induced hemolysis in hepatitis C.

Hemolysis is a frequent adverse effect of ribavirin (RBV). It has been suggested that oxidative stress plays a role, but mechanisms and predictive risk factors for severe forms remain unknown. Markers of redox status were determined in erythrocytes of 34 patients with hepatitis C-four of them with glucose-6-phosphate-dehydrogenase (G6PD) deficiency-before and during treatment with RBV and interferon (IFN) and were compared with 10 healthy control subjects. In addition, erythrocytes were incubated with RBV, and the effects of dipyridamole (DPD), diethylmaleate (DEM), and glutathione ester (GSHE) were studied in vitro. Of the 30 patients without G6PD deficiency who were treated with RBV and IFN-alpha, five developed major hemolysis (Delta hemoglobin > 6 g/dL) and 25 developed minor hemolysis (Delta hemoglobin < 2.5 g/dL). Patients with major hemolysis had lower median pretreatment values of membrane protein sulfhydrils than patients with minor hemolysis (28.4 vs. 36.7 nmol/mg, P <.001). Erythrocytes of G6PD-deficient patients were not more susceptible to RBV-induced hemolysis. In in vitro incubations of erythrocytes, DEM enhanced the RBV-induced decrease of glutathione, protein sulfhydrils, and osmotic resistance. Supplementation of GSHE and DPD prevented the RBV-induced decrease in osmotic resistance, adenosyl triphosphate (ATP), and 2,3-diphosphoglycerate (DPG), the loss of glutathione and protein sulfhydrils, and the formation of thiobarbituric acid reactive substances (TBARs). In conclusion, the data indicate that low membrane protein sulfhydrils prior to therapy but not G6PD deficiency are predictive of RBV-induced major hemolysis. In vitro, GSHE and DPD reduce the RBV-associated oxidative stress in erythrocytes and prevent the increase in osmotic fragility, suggesting that these compounds might decrease the risk of hemolysis in patients.

Adult↗
PubMed1988

Expression of the G6PD locus on the human X chromosome is associated with demethylation of three CpG islands within 100 kb of DNA.

We have previously reported that expression of the G6PD locus is correlated with the methylation status of two islands of CpG dinucleotides which are 3' to the locus and in the 5' region of two adjacent genes of unknown function, P3 and GdX. We have now examined the methylation of a third CpG island in the promoter region of the G6PD gene itself in DNA from males, females and reactivants that express G6PD on the inactive X chromosome. Our results show that expression of the G6PD gene is associated with concordant demethylation of all three CpG islands in this 100-kb region of DNA.

Animals↗
PubMed2004

Novel point mutation in exon 12 of the glucose-6- phosphate dehydrogenase gene: G6PD FLORES.

In Portugal there are a wide variety of G6PD deficiency associated mutations. In an individual from the island of Flores of the Azorean archipelago, we report a new mutation in the G6PD gene that gives rise to a "moderate rate of G6PD deficiency" (12.6% of the normal activity) according to WHO criteria. Direct sequencing revealed a C-->A point mutation at position 1387 with the consequent substitution of an Argine by Serine. We designated this new mutation as G6PD FLORES. The mutation is associated with haplotype I ( - - + + - - ), using six intragenic RFLPs. This information may also be seen as contributing to the clarification of the genetic makeup of the Azorean population, founder mutations, and/or gene flow.

Adolescent↗
PubMed2003

Pycnogenol prevents haemolytic injury in G6PD deficient human erythrocytes.

Glucose6 phosphate dehydrogenase (G6PD) deficiency is the most common X-linked disorder of human erythrocytes where cells have inadequate capacity to destroy peroxides and high susceptibility towards haemolytic changes. Pycnogenol is a proprietary dry extract of the French Maritime pine (Pinus pinaster) bark with high ability to scavenge free radicals. In the present study we have investigated if Pycnogenol can protect G6PD deficient erythrocytes against haemolytic cell damage. Venous blood samples were obtained from six subject of Mediterranean origin with known G6PD deficiency which was also confirmed with standard techniques. Erythrocyte haemolysis in the presence and absence of Pycnogenol was induced either with tert-butylhydroperoxide (t-BHP) or quinine and the haemoglobin release in the supernatant was determined by recording the optical density at 540 nm in a Shimadzu spectrophotometer. Our results have shown that Pycnogenol has protective action against a Xenobiotic chemical induced haemolysis in G6PD deficient human erythrocytes.

Erythrocytes↗
PubMed2000

G6PD deficient cells and the bioreduction of disulfides: effects of DHEA, GSH depletion and phenylarsine oxide.

We used Glucose 6 phosphate dehydrogenase (G6PD) minus cells (89 cells) and G6PD containing cells (K1) to understand the mechanisms of bioreduction of disulfide and the redox regulation of protein and non protein thiols in mammalian cells. The 89 cells reduce hydroxyethyldisulfide (HEDS) to mercaptoethanol (ME) at a slower rate than K1 cells. HEDS reduction results in loss of nonprotein thiols (NPSH) and a decrease in protein thiols (PSH) in 89 cells. The effects are less dramatic with K1 cells. However, the loss of NPSH and PSH in K1 cells are increased in the absence of glucose. Glutathione-depletion with L-BSO partially blocks HEDS reduction in K1 and 89 cells. Treatment with the vicinal thiol reagent phenyl arsenic oxide (PAO) blocks reduction of HEDS in both cells. Surprisingly, dehydroepiandrosterone (DHEA), a known inhibitor of G6PD, inhibits the growth and blocks the reduction of HEDS both in 89 and K1 cells suggesting that its mechanism for inhibition of growth is not G6PD related.

Animals↗
PubMed2000

A new exon 9 glucose-6-phosphate dehydrogenase mutation (G6PD "Rehovot") in a Jewish Ethiopian family with variable phenotypes.

Hereditary nonspherocytic hemolytic anemia (HNSHA) is a rare manifestation of glucose-6-phosphate dehydrogenase (G6PD) gene mutations, caused mainly by mutations located in exon 10 of the G6PD gene and less commonly by mutations in other parts of the gene. A new, exon 9, single-base mutation representing a T --> C transition at cDNA nucleotide 964 was found in three brothers and their carrier mother of Jewish Ethiopian descent. Biochemical characterization of the resultant protein was not performed. Though clinical manifestations included HNSHA in all cases, the severity of hemolysis and the transfusion requirement differed markedly. Severe congenital neutropenia (Kostmann's syndrome)--a disorder never reported before in conjunction with G6PD deficiency--was observed in one case. Levels of white blood cell G6PD activity of the three patients were 0-5% of normal controls. Neutrophil oxidative and bactericidal activities were inherently impaired in the patient with Kostmann's syndrome, but were well preserved in his two siblings.

Anemia, Hemolytic, Congenital Nonspherocytic↗
PubMed1993

Enhanced activity of human G6PD promoter transfected in HeLa cells producing high levels of HIV-1 Tat.

Glucose 6-phosphate dehydrogenase (G6PD) enzyme activity has an important role in the cell defence against oxidative damage produced by hydrogen peroxide, a compound known to activate HIV-1 expression through the intermediate of NF-kappa B. By means of CAT assays, in this paper we show that the Tat protein increases the rate of transcription from the human G6PD promoter in HeLa cells; furthermore, we report a similar effect of Tat on transcription driven from the viral RSV promoter. We did not observe Tat stimulation with the human CMV, SV40 or the basic RSV promoters. Dose-response curves indicate that Tat activates G6PD and RSV through a mechanism different from the major one operating on the HIV-1 LTR promoter. TAR-like structures are not involved, instead a short sequence close to the G6PD transcription start site and the RSV LTR enhancer is a good candidate for mediating the phenomena described in this paper. This sequence has some features in common with the NF-kappa B motif.

Base Sequence↗
PubMed1992

Glucose-6-phosphate dehydrogenase (G6PD) electrophoretic variants and the PvuII polymorphism in southern African populations.

Southern African Bantu-speaking negroid and San populations were examined with regard to the glucose-6-phosphate dehydrogenase (G6PD) PvuII restriction fragment length polymorphism (RFLP) showing alleles of 4 kb and 1.6 kb, called Type 1 and Type 2, respectively. The standardized disequilibrium coefficient for the electrophoretic G6PD types and PvuII alleles in the Southern African population was 0.28. The molecular lesion causing the GdA mutation is the same in the San and Southern African negroid populations. GdA chromosomes are found in association with both the Type 1 and Type 2 alleles, whereas none of the 62 GdB chromosomes from the Southern African populations had the Type 2 allele. Five of the 44 GdB chromosomes studied in the American Black population had the Type 2 allele, indicating that the GdB allele in the two populations may have different origins. The presence of all 3 A- deficiency mutations in the G6PD A gene, in a region where the ancestral population was thought to have predominantly G6PD B, may be explained by their origin in Africa after the divergence of the races.

Africa, Southern↗
PubMed1978

A new variant of human erythrocyte G6PD occurring at a high frequency amongst the population of two villages in The Gambia, West Africa.

During the course of a large survey of red cell G6PD genotypes in The Gambia, a slow electrophoretic variant with reduced enzyme activity was found to occur at a high frequency. This variant, G6PD Gambia, was found in the following genotypic combinations: males; G6PDGam, females; G6PDA+/Gam, G6PDB+/Gam, and G6PDA-/Gam. From the electrophoretic mobility and kinetic characteristics it was concluded that G6PD Gambia was a hitherto unreported variant of G6PD. The frequency of the G6PDGam gene amongst the 1109 individuals examined was 0.024.

Erythrocytes↗
PubMed1978

Three new electrophoretically normal glucose-6-phosphate dehydrogenase variants associated with congenital nonspherocytic hemolytic anemia found in Japan: G6PD Ogikubo, Yokohama, and Akita.

Three new glucose-6-phosphate dehydrogenase (G6PD) variants, which showed electrophoretically normal mobility and were associated with chronic nonspherocytic hemolytic anemia, were found in Japan. G6PD Ogikubo, found in a 17-year-old male whose red cells contained 3% of normal enzyme activity, had normal Km G6P, normal Km NADP, normal utilization of deamino-NADP, decreased heat stability, and a normal pH curve. G6PD Yokohama, characterized from a 15-year-old male, had 1.9% of normal enzyme activity, normal Km G6P, normal Km NADP, low Ki NADPH, normal utilizations of both 2-deoxy-G6P and deamino-NADP, decreased heat stability, and normal pH curve. G6PD Akita, characterized from a 56-year-old male, had an undetectably low activity when hemolysate was examined, normal Km G6P, normal Km NADP, normal Ki NADPH, normal utilizations of both 2-deoxy-G6P and deamino-NADP, decreased heat stability, and normal pH curve. The degree of hemolytic anemia was moderate to mild in all three patients.

Adolescent↗
PubMed1986

The myoblast defect identified in Duchenne muscular dystrophy is not a primary expression of the DMD mutation. Clonal analysis of myoblasts from five double heterozygotes for two X-linked loci: DMD and G6PD.

We previously proposed the hypothesis that the primary expression of the defect in X-linked Duchenne muscular dystrophy (DMD) occurred in the myoblast, or muscle precursor cell. This was based on the observation that the number of viable myoblasts obtained per gram DMD muscle tissue was greatly reduced and those that grew in culture had decreased proliferative capacity and an aberrant distended flat morphology. Here we test that hypothesis by determining whether the expression of the myoblast defect is X-linked. Muscle cells were obtained from five doubly heterozygous carriers of two X-linked loci, DMD and glucose-6-phosphate dehydrogenase (G6PD), and compared with those from five sex- and age-matched controls heterozygous for G6PD only. A total of 1,355 individual clones were determined to be muscle and evaluated at the single cell level for proliferative capacity, morphology, and G6PD isozyme expression. The results demonstrate that the proportion of defective myoblast clones is significantly increased in DMD carriers. However, since this cellular defect does not consistently segregate with a single G6PD phenotype in the myoblast clones derived from any of the carriers, it is unlikely to be the primary expression of the DMD mutant allele.

Adult↗
PubMed1988

G6PD Viangchan: a new glucose 6-phosphate dehydrogenase variant from Laos.

We describe a previously unreported glucose-6-phosphate dehydrogenase-(G6PD) variant. G6PD Viangchan was found in a Laotian immigrant to Calgary, Canada, and was characterized by severe enzyme deficiency, normal electrophoretic mobility, increased pH optimum, and abnormal kinetics for the natural substrates G6PD and NADP, as well as the artificial substrates 2-deoxy G6PD and deamino NADP. The inhibition constant for NADPH was decreased. The subject has no evidence suggesting chronic or episodic hemolysis.

Child↗
PubMed1980

G6PD deficiency in senile cataracts.

The incidence of G6PD deficiency among 338 Thai males with senile cataracts was 5.92% while 446 control Thai males gave an incidence of 6.95%. The figures in females were 16.29% and 14% among 201 senile cataracts females and 200 control females respectively. The age of onset of senile cataracts was not different between the G6PD deficient and G6PD normal groups. The findings indicate that, at least in Thailand, G6PD deficiency in general is not a factor in cataractogenesis.

Cataract↗
PubMed1987

Primary cultures of hepatocytes in serum and hormone-free medium: identification of conditions which stimulate an in vivo-like induction of G6PD.

Recent results from several laboratories suggest that complex interactions between hormones and dietary carbohydrate may be responsible for regulating the induction of several hepatic lipogenic enzymes. Elucidation of these interactions requires the ability to culture hepatocytes for several days in serum-free medium where the hormones or carbohydrate or both present is strictly controlled. The functional response of primary adult rat hepatocytes was examined in a medium without exposure to serum, hormones, or carbohydrates and on three substrata commonly used to culture cells in a defined medium. Hepatocytes cultured on a floating collagen gel in which is embedded a nylon mesh possess cell attachment and morphologic characteristics superior to either cells cultured on a collagen-coated or fibronectin(Fn)-coated substratum. Cells cultured on the gel-mesh system retain insulin responsivity, as measured by protein synthesis rates and glucose-6-phosphate dehydrogenase (G6PD) induction, for at least 6 d in culture. Under these conditions, insulin, dexamethasone, and fructose increase G6PD specific activity to levels comparable to that seen in an induced animal. Hepatocytes cultured on the gel-mesh system tolerate restricted medium conditions better than cells cultured on collagen or Fn-coated substratum, and remain viable for sufficient times to allow, for the first time, full expression and maximal induction (i.e. like in vivo) of G6PD in cultured cells. This system represents a satisfactory model for in vivo liver metabolism and a superior system for studying the effects of hormones and metabolites on G6PD levels, as well as other nutritional-hormonally regulated enzymes.

Animals↗
PubMedDate not supplied

G6PD deficiency in neonates: a prospective study.

One thousand consecutively born babies were screened for G6PD deficiency and observed for seven days for development of jaundice. Frequency of the deficiency was 3.9%, being 5% in males and 2.8% in females. Religion did not have any bearing on the frequency. Parental screening in cases of babies deficient in G6PD enzyme revealed deficiency of the enzyme in majority of the mothers. Hyperbilirubinemia developed in 48.7% of babies having G6PD deficiency : It is recommended that any neonate presenting with jaundice must be screened for G6PD deficiency not only to define the etiology of hyperbilirubinemia but also to prevent future hemolytic episodes.

Female↗
PubMed1996

High-level regulated expression of the human G6PD gene in transgenic mice.

The glucose-6-phosphate dehydrogenase-encoding gene (G6PD) belongs to a group with constitutive expression in all tissues. The regulation of these housekeeping genes is poorly understood, as compared to what is known about many genes whose expression is restricted to a particular tissue or stage of development, and which are often regulated by locus control regions (LCR) able to act over wide distances. In order to identify sequences in human G6PD which are necessary for its expression, we have generated transgenic mice carrying a 20-kb G6PD construct, including only 2.5 kb of upstream and 2.0 kb of downstream flanking sequence. All mice which carried the transgene (TG) expressed it, and the levels of expression detected in a range of tissues from three independent lines of mice were comparable to that of the endogenous murine G6PD. The variation in enzyme activity from tissue to tissue was remarkably similar for both the TG and the endogenous gene, and was shown to be due in both cases to variations in the steady-state mRNA levels.

Animals↗