A novel DO*01 silent allele associated with a nucleotide insertion in a Brazilian patient with anti‐Gy a

Transfusion ◽  
2020 ◽  
Author(s):  
Carolina Bonet Bub ◽  
Maria Giselda Aravechia ◽  
Leandro Dinalli Santos ◽  
Karina V. D. Cruz ◽  
Kennia Duarte ◽  
...  
Keyword(s):  
Brazilian Patient ◽  
Nucleotide Insertion ◽  
Silent Allele

scholarly journals The Maize Unstable factor for orange1 Is a Dominant Epigenetic Modifier of a Tissue Specifically Silent Allele of pericarp color1

Genetics ◽  
2003 ◽  
Vol 163 (3) ◽  
pp. 1135-1146 ◽  
Author(s):  
Surinder Chopra ◽  
Suzy M Cocciolone ◽  
Shaun Bushman ◽  
Vineet Sangar ◽  
Michael D McMullen ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Somatic Mosaicism ◽  
Methylation State ◽  
Vegetative Tissues ◽  
Epigenetic Modifier ◽  
Gene Copies ◽  
Allele Specific ◽  
Silent Allele ◽  
Methylation Patterns ◽  
Variable Penetrance

Abstract We have characterized Unstable factor for orange1 (Ufo1), a dominant, allele-specific modifier of expression of the maize pericarp color1 (p1) gene. The p1 gene encodes an Myb-homologous transcriptional activator of genes required for biosynthesis of red phlobaphene pigments. The P1-wr allele specifies colorless kernel pericarp and red cobs, whereas Ufo1 modifies P1-wr expression to confer pigmentation in kernel pericarp, as well as vegetative tissues, which normally do not accumulate significant amounts of phlobaphene pigments. In the presence of Ufo1, P1-wr transcript levels and transcription rate are increased in kernel pericarp. The P1-wr allele contains approximately six p1 gene copies present in a hypermethylated and multicopy tandem array. In P1-wr Ufo1 plants, methylation of P1-wr DNA sequences is reduced, whereas the methylation state of other repetitive genomic sequences was not detectably affected. The phenotypes produced by the interaction of P1-wr and Ufo1 are unstable, exhibiting somatic mosaicism and variable penetrance. Moreover, the changes in P1-wr expression and methylation are not heritable: meiotic segregants that lack Ufo1 revert to the normal P1-wr expression and methylation patterns. These results demonstrate the existence of a class of modifiers of gene expression whose effects are associated with transient changes in DNA methylation of specific loci.

scholarly journals Structural basis for proficient oxidized ribonucleotide insertion in double strand break repair

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Joonas A. Jamsen ◽  
Akira Sassa ◽  
Lalith Perera ◽  
David D. Shock ◽  
William A. Beard ◽  
...  
Keyword(s):  
Mammalian Cells ◽  
Time Lapse ◽  
Strand Break ◽  
Structural Basis ◽  
End Joining ◽  
Strand Breaks ◽  
Nucleotide Pools ◽  
Nucleotide Insertion ◽  
Non Homologous End Joining

AbstractReactive oxygen species (ROS) oxidize cellular nucleotide pools and cause double strand breaks (DSBs). Non-homologous end-joining (NHEJ) attaches broken chromosomal ends together in mammalian cells. Ribonucleotide insertion by DNA polymerase (pol) μ prepares breaks for end-joining and this is required for successful NHEJ in vivo. We previously showed that pol μ lacks discrimination against oxidized dGTP (8-oxo-dGTP), that can lead to mutagenesis, cancer, aging and human disease. Here we reveal the structural basis for proficient oxidized ribonucleotide (8-oxo-rGTP) incorporation during DSB repair by pol μ. Time-lapse crystallography snapshots of structural intermediates during nucleotide insertion along with computational simulations reveal substrate, metal and side chain dynamics, that allow oxidized ribonucleotides to escape polymerase discrimination checkpoints. Abundant nucleotide pools, combined with inefficient sanitization and repair, implicate pol μ mediated oxidized ribonucleotide insertion as an emerging source of widespread persistent mutagenesis and genomic instability.

scholarly journals Conformational landscapes of DNA polymerase I and mutator derivatives establish fidelity checkpoints for nucleotide insertion

2013 ◽  
Vol 4 (1) ◽  
Author(s):  
Johannes Hohlbein ◽  
Louise Aigrain ◽  
Timothy D. Craggs ◽  
Oya Bermek ◽  
Olga Potapova ◽  
...  
Keyword(s):  
Dna Polymerase ◽  
Dna Polymerase I ◽  
Nucleotide Insertion ◽  
Polymerase I

Molecular characterization of five novel Wx-A1 alleles in common wheat including one silent allele by transposon insertion

Plant Science ◽  
2021 ◽  
Vol 305 ◽  
pp. 110843
Author(s):  
Juan B. Alvarez ◽  
Laura Castellano ◽  
Ana B. Huertas-García ◽  
Carlos Guzmán
Keyword(s):  
Molecular Characterization ◽  
Common Wheat ◽  
Transposon Insertion ◽  
Silent Allele

scholarly journals Mechanism of Metronidazole Resistance inHelicobacter pylori: Comparison of the rdxA Gene Sequences in 30 Strains

2000 ◽  
Vol 44 (8) ◽  
pp. 2207-2210 ◽  
Author(s):  
Nadia Maggi Solcà ◽  
Marco Valerio Bernasconi ◽  
Jean-Claude Piffaretti
Keyword(s):  
Phylogenetic Analysis ◽  
Helicobacter Pylori ◽  
Amino Acid ◽  
Resistant Strain ◽  
Point Mutations ◽  
Housekeeping Genes ◽  
Amino Acid Substitutions ◽  
Metronidazole Resistance ◽  
Nucleotide Mutation ◽  
Nucleotide Insertion

ABSTRACT The rdxA gene of 30 independently isolatedHelicobacter pylori strains was sequenced. A comparison of the rdxA sequences revealed a higher percentage of amino acid substitutions in the corresponding protein than in other housekeeping genes. Out of 122 point mutations, 41 were missense and 4 were nonsense. A resistant strain with a nucleotide insertion in therdxA sequence was also found. With the exception of the point mutations and the insertion generating a stop signal, no particular nucleotide mutation or amino acid substitution could be associated to metronidazole resistance. Moreover, phylogenetic analysis of the 30 nucleotide sequences did not demonstrate specific clusters associated with the resistance phenotype.

C1-inhibitor gene nucleotide insertion causes type II hereditary angio-oedema

1993 ◽  
Vol 92 (2) ◽  
Author(s):  
Z. Siddique ◽  
A.R. McPhaden ◽  
K. Whaley
Keyword(s):  
Type Ii ◽  
C1 Inhibitor ◽  
Nucleotide Insertion ◽  
Inhibitor Gene

scholarly journals beta-thalassemia intermedia in a Brazilian patient with - 101(C > T) and codon 39 (C > T) mutations

2003 ◽  
Vol 121 (1) ◽  
pp. 28-30
Author(s):  
Sylvia Morais de Sousa ◽  
Letícia Khater ◽  
Luís Antônio Peroni ◽  
Karine Miranda ◽  
Marcelo Jun Murai ◽  
...  
Keyword(s):  
Clinical Course ◽  
Globin Gene ◽  
Fetal Hemoglobin ◽  
Hypochromic Anemia ◽  
Beta Thalassemia ◽  
Beta Globin ◽  
Thalassemia Intermedia ◽  
Mean Cell Volume ◽  
Molecular Alterations ◽  
Brazilian Patient

CONTEXT: We verified molecular alterations in a 72-year-old Brazilian male patient with a clinical course of homozygous beta-thalassemia intermedia, who had undergone splenectomy and was surviving without regular blood transfusions. The blood cell count revealed microcytic and hypochromic anemia (hemoglobin = 6.5 g/dl, mean cell volume = 74 fl, mean cell hemoglobin = 24 pg) and hemoglobin electrophoresis showed fetal hemoglobin = 1.3%, hemoglobin A2 = 6.78% and hemoglobin A = 79.4%. OBJECTIVE: To identify mutations in a patient with the symptoms of beta-thalassemia intermedia. DESIGN: Molecular inquiry into the mutations possibly responsible for the clinical picture described. SETTING: The structural molecular biology and genetic engineering center of the Universidade Estadual de Campinas, Campinas, Brazil. PROCEDURES: DNA extraction was performed on the patient's blood samples. The polymerase chain reaction (PCR) was done using five specific primers that amplified exons and the promoter region of the beta globin gene. The samples were sequenced and then analyzed via computer programs. RESULTS: Two mutations that cause the disease were found: -101 (C > T) and codon 39 (C > T). CONCLUSIONS: This case represents the first description of 101 (C > T) mutation in a Brazilian population and it is associated with a benign clinical course.

scholarly journals The genetics of Dacus oleae: III. Amount of variation at two esterase loci in a Greek population

1969 ◽  
Vol 14 (3) ◽  
pp. 249-258 ◽  
Author(s):  
E. Zouros ◽  
C. B. Krimbas
Keyword(s):  
Allele Frequency ◽  
Fruit Fly ◽  
Olive Fruit Fly ◽  
Allele Frequency Distribution ◽  
Natural Conditions ◽  
Dacus Oleae ◽  
Random Drift ◽  
Selective Neutrality ◽  
Esterase Loci ◽  
Silent Allele

Two polymorphic esterase loci, EstA and EstB, of the olive-fruit fly Dacus oleae were studied in a natural population. The analysis of about 500 individuals revealed the presence of 15 alleles for EstA and 12 alleles for EstB. A ‘silent’ allele was found segregating at both loci. Segregation data for most of the alleles are presented. The allele frequency distribution follows the same pattern at both loci: one allele of each gene has a frequency of nearly 0·50, a few have frequencies between 0·05 and 0·15 and many are below 0·05. Two main hypotheses, those of overdominance and selective neutrality, were examined in order to explain these polymorphisms. We deduced that under both hypotheses a relatively high mutation rate is necessary to balance the result of random drift. This rate was estimated to be higher than 4 × 10−5 for the EstA locus. Since homozygotes for the ‘silent’ allele at the first or at the second locus were found in the population in expected frequencies, it was concluded that these alleles are not inferior to active ones under natural conditions.

Identification of a novel missense mutation in Brazilian patient with a severe form of mucopolysaccharidosis type IVA

2013 ◽  
Vol 108 (2) ◽  
pp. S59-S60
Author(s):  
Sandra Leistner-Segal ◽  
Francyne Kubaski ◽  
Ana Carolina Brusius-Facchin ◽  
Heloísa M.C. Palhares ◽  
Marly Aparecida Spadotto Balarin ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Severe Form ◽  
Mucopolysaccharidosis Type ◽  
Brazilian Patient ◽  
Mucopolysaccharidosis Type Iva
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