Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.1.30.2 (endonuclease)
 18,621 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Infantile-onset glycogen storage disease type II, or Pompe disease, results from a genetic deficiency of the lysosomal enzyme acid alpha glucosidase (GAA). Sequencing of the cDNA from a cell line (GM 244) derived from a patient with Pompe disease demonstrated a T953-to-C transition that predicted a methionine-to-threonine substitution at codon 318. The basepair substitution resulted in loss of restriction-endonuclease sites for NcoI and StyI. Analysis of genomic DNA revealed both a normal and an abnormal NcoI fragment, indicating that the patient was a genetic compound. NcoI and StyI digestion of cDNA, amplified by PCR from reverse-transcribed RNA, demonstrated that greater than 95% of the GAA mRNA in GM 244 was derived from the allele carrying the missense mutation. The missense mutation was uncommon, since it was not detected in 37 additional GAA-deficient chromosomes, as determined by digestion of genomic DNA with NcoI and hybridization. The amino acid substitution predicts a new potential site for N-linked glycosylation, as well as major changes in secondary structure of the protein. We could confirm that the mutation was responsible for the enzyme deficiency by demonstrating that a hybrid minigene containing the mutation did not express GAA enzyme activity after transient gene expression. We have therefore now provided the first identification of a single-basepair missense mutation in a patient with Pompe disease and furthermore have demonstrated that the patient is a genetic compound with the second allele barely expressing mRNA.
 ...
PMID:Identification of a missense mutation in one allele of a patient with Pompe disease, and use of endonuclease digestion of PCR-amplified RNA to demonstrate lack of mRNA expression from the second allele. 165 92

Gene cluster CYP2D controls the biosynthesis of enzyme CYP2D6, which is responsible for the polymorphic oxidation of sparteine, debrisoquine and related drugs. This cluster consists of the functional gene D6 and of two pseudogenes, D7 and D8. RFLP Bam HI analysis of CYP2D in 37 unrelated and eight related Ngawbe Guaymi Amerindians of Panama showed a polymorphism characterized by the presence of two alleles: 4.7 + 7.9 and 2.3 + 6.0 (frequencies: 0.63 and 0.37, respectively, n = 35 unrelated subjects). The possible genotypes for these alleles follow the Hardy-Weinberg distribution (chi 2 = 1.76; 0.10 < p < 0.25). All PMs of sparteine or debrisoquine (n = 7) were homozygotes for the second allele, but not all homozygotes (n = 10) were PMs, so there was not an exclusive association between the Bam HI genotype and the observed phenotype. A similar analysis with the endonuclease Xba I proved to be non-informative in relation to phenotype, since all subjects (n = 40) showed only the 29 kb allele. Allele-specific PCR studies of selected subjects indicated the existence of the CYP2D6B allele (freq = 0.17; C.I.95% = 0.085, 0.29; n = 30 unrelated subjects), in addition to the wild-type. The mutant CYP2D6B allele was responsible for the enzyme deficiency present in PMs. Its presence in Amerindians suggests that this allele has a far more ancient evolutionary history than previously thought. The over-all RFLP and PCR analyses point to a diminished genetic diversity for the Ngawbe subjects, consistent with their demographic history and population genetics.
 ...
PMID:Evolutionary pharmacogenetics of CYP2D6 in Ngawbe Guaymi of Panama: allele-specific PCR detection of the CYP2D6B allele and RFLP analysis. 790 9

Phosphoglucomutase 1 (PGM1) deficiency is a stable characteristic of the erythroleukaemic cell line, K562, whereas the activity of the isozymes of the other two PGM loci (PGM2 and PGM3) is slightly elevated. In this study the molecular basis of PGM1 deficiency was investigated by a combined approach utilising protein electrophoresis, immunodetection, cytogenetic techniques, and DNA and RNA analysis. Isoelectric focusing and activity staining confirmed that K562 has no detectable PGM1 activity. Immunoblot analysis of extracts, separated by isoelectric focusing, starch gel and SDS gel electrophoresis, using monospecific anti-PGM1 antibodies showed that K562 contained no detectable immunoreactive material. Karyotype analysis revealed the presence of two intact chromosomes 1 and a derivative chromosome 1, der(1)t(1;11), each of which carried a copy of the PGM1 gene as demonstrated by fluorescence in situ hybridization using a PGM1 cosmid as probe. Southern blot analysis using a PGM1 cDNA clone as probe suggested that the PGM1 genes had not been subject to any gross structural rearrangements. We were also able to determine that K562 is type PGM1 2+1+ by restriction endonuclease analysis of genomic DNA. Very low levels of PGM1 mRNA which appeared to be full length transcripts were detected in K562 using a reverse transcriptase PCR technique. We conclude that the most likely cause of PGM1 enzyme deficiency in K562 is abnormal regulation of transcription.
 ...
PMID:Molecular and cytological investigations of phosphoglucomutase (PGM1) in the K562 cell line. 917 17

Background: Myo-adenylate deaminase deficiency (mADD) is the most common enzyme deficiency restricted to skeletal muscle, with a frequency of 1-2% in frozen muscle biopsies and complaints of easy fatigue and muscle cramping on exertion. A double C > T transition at coding bases 34 in exon 2 and 143 in exon 3 is the main cause of mADD. A 1-day assay using allele-specific oligomers and no isotope would be valuable for single cases. Methods and Results: Downstream primers with penultimate mismatch and 3' terminus matching the mutant or the normal base in exons 2 and 3 are used with a common upstream primer for each exon, to give amplimers of 150 bp for exon 2 and 200 bp for exon 3. A short common primer further downstream in exon 3 provides a competing 300-bp apmlimer whose product contribution is readily controlled by adjusting the annealing temperature. The entire procdure could be done in 1 day: DNA isolation, polymerase chain reaction (PCR), electrophoresis in agarose gel with ethidium bromide, and visualization by ultraviolet light. Deficient individuals have bands only with the mutant primers, normal persons have bands only with the normal primers, and heterozygotes (carriers) show bands with both primer sets. The empty slots show the 300-bp competing band, proving the PCR amplified the correct template. Allele-specific oligomers PCR results were verfied by dot blots and by restriction endonuclease analysis of exon 2. Conclusions: A simple and reliable allele-specific PCR assay using DNA from blood (or muscle) is now available for the diagnosis of individual cases of mADD caused by the common double-mtant AMPD1 gene, including the rare instances arising from homologous recombination between the two mutations.
 ...
PMID:A Competitive Allele-specific Oligomers Polymerase Chain Reaction Assay for the cis Double Mutation in AMPD1 That Is the Major Cause of Myo-adenylate Deaminase Deficiency. 1046 99

Pyruvate kinase (PK) deficiency is a rare red cell glycolytic enzymopathy. The purpose of the present investigation was to offer prenatal diagnosis for PK deficiency to a couple who had a previous child with severe enzyme deficiency and congenital non-spherocytic hemolytic anemia. PK deficiency was identified in the family by assaying the enzyme activity in red cells. Chorionic villus sampling was performed in an 11-week gestation and the mutation was located in exon 10 of the PKLR gene characterized by polymerase chain reaction and using restriction endonuclease digestion with the MspI enzyme, which was confirmed by DNA sequencing on the ABI 310 DNA sequencer. Both the parents were heterozygous for the 1436G-->A [479 Arg-->His] mutation in exon 10 and the proband was homozygous for this mutation. The fetus was also heterozygous for this mutation and the pregnancy was continued. Prenatal diagnosis allowed the parents with a severely affected child with PK deficiency to have the reproductive choice of having the fetus tested in a subsequent pregnancy.
 ...
PMID:First-trimester prenatal diagnosis of pyruvate kinase deficiency in an Indian family with the pyruvate kinase-Amish mutation. 1795 71