Use of repetitive DNA for diagnosis of chromosomal rearrangements

1983 ◽  
Vol 64 (4) ◽  
pp. 339-342 ◽  
Author(s):  
R. D. Burk ◽  
Judith Stamberg ◽  
K. E. Young ◽  
K. D. Smith
Keyword(s):  
Repetitive Dna ◽  
Chromosomal Rearrangements

Genotype- and Cell-Specific Dynamics of Tandem Repeat Patterns in Aegilops speltoides Tausch (Poaceae, Triticeae)

2017 ◽  
Vol 153 (2) ◽  
pp. 105-116 ◽  
Author(s):  
Olga Raskina
Keyword(s):  
Repetitive Dna ◽  
Tandem Repeat ◽  
Structural Integrity ◽  
Wide Spectrum ◽  
Chromosomal Rearrangements ◽  
Wild Plant ◽  
Aegilops Speltoides ◽  
Nonhomologous Recombination ◽  
In The Wild ◽  
The Impact

In wild plant populations, chromosome rearrangements lead to the wide intraspecific polymorphisms in the abundance and patterns of highly repetitive DNA. However, despite the large amount of accumulated data, the impact of the complex repetitive DNA fraction on genome reorganization and functioning and the mechanisms balancing and maintaining the structural integrity of the genome are not fully understood. Homologous recombination is thought to play a key role in both genome reshuffling and stabilization, while the contribution of nonhomologous recombination seems to be undervalued. Here, tandem repeat patterns and dynamics during pollen mother cell development were addressed, with a focus on the meiotic recombination that determines chromosome/genome repatterning and stabilization under cross-pollination and artificial hybridization in wild goatgrass, Aegilops speltoides. Native plants from contrasting allopatric populations and artificially created intraspecific hybrids were investigated using a FISH approach. Cytogenetic analysis uncovered a wide spectrum of genotype- and cell-specific chromosomal rearrangements, suggesting intensive repatterning of both parental and hybrid genomes. The data obtained provide evidence that repetitive elements serve as overabundant and ubiquitous resources for maintaining chromosome architecture/genome integrity through homologous and nonhomologous recombination at the intraorganismal level, and genotype-specific repatterning underlies intrapopulation polymorphisms and intraspecific diversification in the wild.

Repetitive DNA and chromosomal rearrangements: speciation-related events in plant genomes

2008 ◽  
Vol 120 (3-4) ◽  
pp. 351-357 ◽  
Author(s):  
O. Raskina ◽  
J.C. Barber ◽  
E. Nevo ◽  
A. Belyayev
Keyword(s):  
Repetitive Dna ◽  
Chromosomal Rearrangements ◽  
Plant Genomes

scholarly journals Molecular Composition of Heterochromatin and Its Contribution to Chromosome Variation in the Microtus thomasi/Microtus atticus Species Complex

Genes ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 807
Author(s):  
Michail Rovatsos ◽  
Juan Alberto Marchal ◽  
Eva Giagia-Athanasopoulou ◽  
Antonio Sánchez
Keyword(s):  
Repetitive Dna ◽  
Species Complex ◽  
Sex Chromosome ◽  
Chromosomal Rearrangements ◽  
Chromosome Morphology ◽  
Dna Motifs ◽  
Telomeric Sequences ◽  
Chromosome Races ◽  
Chromosomal Races ◽  
Dna Elements

The voles of the Microtus thomasi/M. atticus species complex demonstrate a remarkable variability in diploid chromosomal number (2n = 38–44 chromosomes) and sex chromosome morphology. In the current study, we examined by in situ hybridization the topology of four satellite DNA motifs (Msat-160, Mth-Alu900, Mth-Alu2.2, TTAGGG telomeric sequences) and two transposons (LINE, SINE) on the karyotypes of nine chromosome races (i.e., populations with unique cytogenetic traits) of Microtus thomasi, and two chromosomal races of M. atticus. According to the topology of the repetitive DNA motifs, we were able to identify six types of biarmed chromosomes formed from either Robertsonian or/and tandem fusions. In addition, we identified 14 X chromosome variants and 12 Y chromosome variants, and we were able to reconstruct their evolutionary relations, caused mainly by distinct mechanisms of amplification of repetitive DNA elements, including the telomeric sequences. Our study used the model of the Microtus thomasi/M. atticus species complex to explore how repetitive centromeric content can alter from chromosomal rearrangements and can shape the morphology of sex chromosomes, resulting in extensive inter-species cytogenetic variability.

scholarly journals Variability of the genome size in coniferous plant in extreme environmental conditions

1970 ◽  
pp. 37-41
Author(s):  
T. S. Sedelnikova
Keyword(s):  
Genome Size ◽  
Repetitive Dna ◽  
Dna Sequences ◽  
Environmental Conditions ◽  
Nuclear Dna ◽  
Chromosomal Rearrangements ◽  
Repetitive Dna Sequences ◽  
Dna Variation ◽  
Nuclear Dna Variation ◽  
Rna Genes

Aim. The features of genome size transformation in conifers growing in extreme environmental conditions are reviewed. Conclusions. Conifers have a very large genome. The main resources of genome size modifications of conifers under extreme environmental conditions are: variability of the chromosome numbers (polyploidy, aneuploidy; mixoploidy), occurrence of B-chromosomes and increasing of its numbers, changes of the content of nuclear DNA, variation of the repetitive DNA sequences (microsatellites, ribosomal RNA genes, transposable elements – retrotransposons), and the chromosomal rearrangements. These features are also components of the epigenetic system which defines the adaptability of the genome changes when exposed to stressful environmental factors. Keywords: Pinophyta, genome, repetitive DNA sequences, epigenetic system.

scholarly journals Extensive chromosomal fissions and repetitive DNA accumulation shaped the atypical karyotypes of two Ramphastidae (Aves: Piciformes) species

2020 ◽  
Vol 130 (4) ◽  
pp. 839-849 ◽  
Author(s):  
Rafael Kretschmer ◽  
Ivanete De Oliveira Furo ◽  
Marcelo De Bello Cioffi ◽  
Ricardo José Gunski ◽  
Analía Del Valle Garnero ◽  
...  
Keyword(s):  
Repetitive Dna ◽  
Diploid Number ◽  
Driving Forces ◽  
Chromosomal Rearrangements ◽  
Chromosome 1 ◽  
Z Chromosome ◽  
Chromosome 3 ◽  
Ancestral Karyotype ◽  
Chicken Chromosome ◽  
Representative Species

Abstract In contrast to the ‘avian-like’ diploid number (2n = 80), most toucans and aracaris (Piciformes: Ramphastidae) have divergent karyotypes, exhibiting a higher 2n. To identify the chromosomal rearrangements that shaped the karyotype of these species, we applied chicken macrochromosome paints 1–10 and 11 microsatellite sequences to the chromosomes of two representative species, Pteroglossus inscriptus and Ramphastos tucannus tucannus. Paints of chicken chromosomes revealed that at least the first five ancestral chromosomes have undergone fissions, and a fusion between a segment of chicken chromosome 1 and a segment from chromosome 3 occurred in both species. The microsatellite sequences were accumulated mainly in the Z chromosome and in several microchromosomes in both species. These results suggest that the genomes of the Ramphastidae have been shaped by extensive fissions and repetitive DNA accumulation as the main driving forces leading to the higher 2n as found in these species. Furthermore, our results suggest that the putative ancestral karyotype of Ramphastidae already had a high diploid number, probably close to 2n = 112, similar to that observed in P. inscriptus and R. t. tucannus.

scholarly journals Comparative cytogenetics among Leporinus friderici and Leporellus vittatus populations (Characiformes, Anostomidae): focus on repetitive DNA elements

2019 ◽  
Vol 13 (2) ◽  
pp. 105-120 ◽  
Author(s):  
Thais Aparecida Dulz ◽  
Carla Andrea Lorscheider ◽  
Viviane Demetrio Nascimento ◽  
Rafael Bueno Noleto ◽  
Orlando Moreira-Filho ◽  
...  
Keyword(s):  
Repetitive Dna ◽  
Dna Sequences ◽  
Chromosomal Rearrangements ◽  
5S Rdna ◽  
Neotropical Fish ◽  
Comparative Cytogenetics ◽  
Fish Family ◽  
Telomere Sequence ◽  
Dna Elements ◽  
Chromosomal Changes

Anostomidae are a neotropical fish family rich in number of species. Cytogenetically, they show a conserved karyotype with 2n = 54 chromosomes, although they present intraspecific/interspecific variations in the number and chromosomal location of repetitive DNA sequences. The aim of the present study was to perform a comparative description of the karyotypes of two populations of Leporinusfriderici Bloch, 1794 and three populations of Leporellusvittatus Valenciennes, 1850. We used conventional cytogenetic techniques allied to fluorescence in situ hybridization, using 18S ribosomal DNA (rDNA) and 5S rDNA, a general telomere sequence for vertebrates (TTAGGG)n and retrotransposon (RTE) Rex1 probes. The anostomids in all studied populations presented 2n = 54 chromosomes, with a chromosome formula of 32m + 22sm for L.friderici and 28m + 26sm for L.vittatus. Variations in the number and location of the 5S and 18S rDNA chromosomal sites were observed between L.friderici and L.vittatus populations and species. Accumulation of Rex1 was observed in the terminal region of most chromosomes in all populations, and telomere sequences were located just on all ends of the 54 chromosomes in all populations. The intraspecific and intergeneric chromosomal changes occurred in karyotype differentiation, indicating that minor chromosomal rearrangements had present in anostomid species diversification.

Electron Microscopy and image analysis of nucleo-protein complexes

1994 ◽  
Vol 52 ◽  
pp. 88-89
Author(s):  
E. H. Egelman ◽  
X. Yu
Keyword(s):  
Electron Microscopy ◽  
Image Analysis ◽  
Normal Cell ◽  
Genetic Recombination ◽  
Protein Complexes ◽  
Chromosomal Rearrangements ◽  
Reca Protein ◽  
E Coli ◽  
Helical Polymer ◽  
Specific Protease

The RecA protein of E. coli has been shown to mediate genetic recombination, regulate its own synthesis, control the expression of other genes, act as a specific protease, form a helical polymer and have an ATPase activity, among other observed properties. The unusual filament formed by the RecA protein on DNA has not previously been shown to exist outside of bacteria. Within this filament, the 36 Å pitch of B-form DNA is extended to about 95 Å, the pitch of the RecA helix. We have now establishedthat similar nucleo-protein complexes are formed by bacteriophage and yeast proteins, and availableevidence suggests that this structure is universal across all of biology, including humans. Thus, understanding the function of the RecA protein will reveal basic mechanisms, in existence inall organisms, that are at the foundation of general genetic recombination and repair.Recombination at this moment is assuming an importance far greater than just pure biology. The association between chromosomal rearrangements and neoplasms has become stronger and stronger, and these rearrangements are most likely products of the recombinatory apparatus of the normal cell. Further, damage to DNA appears to be a major cause of cancer.

DNA methylation in satellite repeats disorders

2019 ◽  
Vol 63 (6) ◽  
pp. 757-771 ◽  
Author(s):  
Claire Francastel ◽  
Frédérique Magdinier
Keyword(s):  
Dna Methylation ◽  
Human Genome ◽  
Repetitive Dna ◽  
Dna Sequences ◽  
Satellite Repeats ◽  
Tremendous Progress ◽  
Genes Encoding ◽  
Dna Elements ◽  
Near Future

Abstract Despite the tremendous progress made in recent years in assembling the human genome, tandemly repeated DNA elements remain poorly characterized. These sequences account for the vast majority of methylated sites in the human genome and their methylated state is necessary for this repetitive DNA to function properly and to maintain genome integrity. Furthermore, recent advances highlight the emerging role of these sequences in regulating the functions of the human genome and its variability during evolution, among individuals, or in disease susceptibility. In addition, a number of inherited rare diseases are directly linked to the alteration of some of these repetitive DNA sequences, either through changes in the organization or size of the tandem repeat arrays or through mutations in genes encoding chromatin modifiers involved in the epigenetic regulation of these elements. Although largely overlooked so far in the functional annotation of the human genome, satellite elements play key roles in its architectural and topological organization. This includes functions as boundary elements delimitating functional domains or assembly of repressive nuclear compartments, with local or distal impact on gene expression. Thus, the consideration of satellite repeats organization and their associated epigenetic landmarks, including DNA methylation (DNAme), will become unavoidable in the near future to fully decipher human phenotypes and associated diseases.

The experience of holding the cycles of assisted reproductive technology with defrost, a biopsy, genetic study and refreezing of embryos in patients with multiple unsuccessful implantations

2016 ◽  
pp. 166-170
Author(s):  
Y.V. Masliy ◽  
◽  
I.O. Sudoma ◽  
P.S. Mazur ◽  
D.A. Mykytenko ◽  
...  
Keyword(s):  
Chromosomal Rearrangements ◽  
Genetic Diagnosis ◽  
Morphological Characteristics ◽  
Implantation Rate ◽  
Ovarian Response ◽  
Reproductive Technologies ◽  
Comparative Genome Hybridization ◽  
Comparative Genome ◽  
Vitro Fertilization

The objective: to study the possibility of using frozen blastocysts for biopsy and genetic testing and performance measurement transfer euploeded 5–7-day-old embryos after thawing, biopsies, refreezing and thawing in patients with unsuccessful implantation. Patients and methods. The object of the study was the group of patients with repeated failure of implantation (4) in programs of auxiliary reproductive technologies (ART), subject to transfer to the uterus in total (i.e. in all the programs) for at least 6 good quality embryos based on morphological characteristics). All women had sufficient ovarian reserve. The patient was treated for infertility within the ART programs of the clinic of reproductive medicine "Nadiya" in the period from 2006 to 2016. The sample included couples who were not carriers of chromosomal rearrangements, without anomalies of the uterus (congenital and acquired: a doubling of the uterus, one-horned uterus, intrauterine membrane, synechia, submucous myoma of the uterus). All women had a positive ovarian response to controlled stimulation with gonadotropins (at least 7 oocytes) and a sufficient number of cryopreserved embryos. The first group (G1) included 64 women who trophectodermal a biopsy was performed on fresh blastocysts (in a loop controlled ovarian hyperstimulation). The second group (G2) were included 31 women who underwent thawing previously cryopreserved blastocysts trophectodermal re-biopsy and vitrification of blastocysts. Results. It was found that the performance of transfers euploid embryos that were vitrified, bioptrone and revitriphted, a little lower than those that were bioptrone fresh and vitrified only once. At the same time computationa genetic diagnosis previously vitrified blastocysts using comparative genome hybridization in patients with recurrent failed implantation allows to obtain a reasonable pregnancy rate (58%), implantation rate (33.3 %) and the birth of living children (45.1 %). Conclusion. Reprising biopropane embryos does not cause significant destructive impact and allows you to achieve pregnancy and birth of the alive child. Key words: in vitro fertilization, reusable unsuccessful implantation, a method of comparative genome hybridization, refreezing.

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