Formation of dicentric chromosomes fragments chromosome aberrations. Medical search. Frequent questions

The test substance is considered to cause structural chromosomal aberrations in cultured mammalian cells according to an in vitro OECD 473 chromosomal aberration assay. (europa.eu)
A type of chromosomal aberration involving DNA BREAKS. (lookformedical.com)

It is observed that both biological effects and epidemiological effects appear to be the same or very similar from ELF exposure and from RF/MW exposures, including calcium ion efflux, melatonin reduction, DNA strand breakage, chromosome aberrations, leukaemia, brain cancer, breast cancer, miscarriage and neurological effects. (whale.to)
or other CHROMOSOME BREAKAGE related aberrations. (lookformedical.com)
Spontaneous CHROMOSOME BREAKAGE is a feature of this disease along with predisposition to LEUKEMIA. (lookformedical.com)

It appears that lepidopteran chromosomes can tolerate telomere loss without the drastic effects that this has on chromosomes in other orders. (wikipedia.org)

ABL1 fusion, in which a paracentric inversion within the short arm of chromosome 12 (12p) and a translocation between the long arm of a chromosome 9 and the 12p with the inversion were involved. (bvsalud.org)
Emanuel syndrome (ES), caused by an unbalanced translocation between chromosomes 11 and 22, has lacked a reliable prenatal screening option for families with a carrier parent. (bvsalud.org)

The authors recently mapped a susceptibility locus for autism to chromosome region 2q24-q33 (MIM number 606053). (neurotransmitter.net)

During early prophase the broken chromosome undergoes normal replication, but during metaphase the broken ends can fuse leading to the formation of a dicentric chromosome and an acentric fragment. (wikipedia.org)
Eukaryotic DNA replication initiates at multiple origin sites along each chromosome and terminates when replication forks (RFs) from adjacent origins converge. (elifesciences.org)
An increased tendency to acquire CHROMOSOME ABERRATIONS when various processes involved in chromosome replication, repair, or segregation are dysfunctional. (lookformedical.com)
A terminal section of a chromosome which has a specialized structure and which is involved in chromosomal replication and stability. (lookformedical.com)

In species with large kinetochore plates, the fragments may persist for a number of mitotic cell divisions, and can even be transmitted through germ cells to the next generation. (wikipedia.org)

The test item did not induce a significant level of chromosome aberrations in Chinese hamster V79 cells in the performed experiments with and without metabolic activation. (europa.eu)

In the second half of the cell cycle the chromosomes clone themselves so that at mitosis, cell division, each cell has a full set of chromosomes. (whale.to)

Almost every chromosome is affected by numeric or structural aberrations. (neurotransmitter.net)

The kinetochore plates are large and cover a significant portion of the chromosome length, ensuring that more radiation-induced breaks will not lead to the loss of chromosome fragments as is typical in species with monocentric chromosomes. (wikipedia.org)

Any substance that damages DNA or chromosomes, or changes genetic activity, is genotoxic because it is acting on the same material, i.e. the DNA molecule. (whale.to)

The primary lesion leading to a dominant lethal mutation is a break in the chromosome, in this case, induced by radiation. (wikipedia.org)
Since the early years of radiobiology the cellular effects of ionizing radiation have been studied in the context of induced chromosomal aberrations, and early models of radiation action were largely based upon such studies (Savage 1996). (nationalacademies.org)

Lepidopteran chromosomes possess a localized kinetochore plate to which the spindle microtubules attach during cell division. (wikipedia.org)
Prenatal cell-free DNA screening (cfDNA) can identify fetal chromosome abnormalities beyond common trisomies. (bvsalud.org)
In a normally diploid cell (DIPLOIDY) the loss of a chromosome pair is termed nullisomy (symbol: 2N-2), the loss of a single chromosome is MONOSOMY (symbol: 2N-1), the addition of a chromosome pair is tetrasomy (symbol: 2N+2), the addition of a single chromosome is TRISOMY (symbol: 2N+1). (lookformedical.com)
A type of CELL NUCLEUS division by means of which the two daughter nuclei normally receive identical complements of the number of CHROMOSOMES of the somatic cells of the species. (lookformedical.com)

In conclusion, our data reveal classes of rearrangements that are specific to BRCA1 or BRCA2 deficiency as a source of cytogenetic aberrations in HR-deficient cells. (bvsalud.org)
The chromosomal constitution of cells which deviate from the normal by the addition or subtraction of CHROMOSOMES, chromosome pairs, or chromosome fragments. (lookformedical.com)

The acentric fragment is frequently lost, while the dicentric fragment forms a bridge at anaphase leading to another chromosomal break. (wikipedia.org)

They then fold themselves into the set of chromosomes that are so large that they can be seen in powerful microscopes. (whale.to)

Following fusion, nuclear divisions begin, and a break in a chromosome can have drastic effects on the viability of the embryo as development proceeds. (wikipedia.org)

The acentric fragment is frequently lost, while the dicentric fragment forms a bridge at anaphase leading to another chromosomal break. (wikipedia.org)
Nontargeted effects include radiation-induced genomic instability (RIGI) which is observed in the progeny of cells exposed to ionizing radiation and can be manifested in different ways, including chromosomal instability and micronucleus (MN) formation. (genome-integrity.org)
[1] , [2] These nontargeted effects, including radiation-induced genomic instability (RIGI) which is observed in the progeny of cells exposed to ionizing radiation, can be manifested in different ways such as gene mutations, chromosomal instability, micronucleus (MN) formation, and an enhanced death rate. (genome-integrity.org)
The aim of the present study was to evaluate genomic instability by analyzing chromosomal aberrations, micronuclei, and 53BP1 DNA repair foci in peripheral blood lymphocytes of radiologists. (bvsalud.org)
However, our results showed an increased frequency of micronuclei and various types of chromosomal aberrations including dicentrics in interventional radiologists. (bvsalud.org)
Two cytogenetic endpoints were used, namely Chromosomal Aberrations assay (CA) and Micronucleus test (MN). (waocp.com)
Whereas, treatment of CHO cell lines with different concentrations of ZER along with 2.5 µM Cisplatin was found to reduce chromosomal aberrations, suggesting an antagonistic genotoxic effect. (waocp.com)
ecDNA was thought, until very recently, to be a rare characteristic of tumors (1.4% of tumors according the Mittelman database of chromosomal aberrations), of unclear significance but current evidence shows that highly amplified, oncogene-containing ecDNAs are common in cancer (25 out of 29 types) [ 8 ]. (silverchair.com)
The test substance is considered to cause structural chromosomal aberrations in cultured mammalian cells according to an in vitro OECD 473 chromosomal aberration assay. (europa.eu)

The centromere is a region, often found in the middle of the chromosome , involved in cell division and the control of gene expression . (wikidoc.org)
The centromere is together with telomeres and origin of replications one of the essential parts of any eukaryotic chromosomes. (wikidoc.org)
A centromere functions in sister chromatid adhesion, kinetochore formation, and pairing of homologous chromosomes . (wikidoc.org)
The centromere is also where kinetochore formation takes place: proteins bind on the centromeres that form an anchor point for the spindle formation required for the pull of chromosomes toward the centrioles during the anaphase and telophase of mitosis. (wikidoc.org)
When the centromere doesn't function properly, the chromosomes don't align and separate properly, resulting in the wrong number of chromosomes in the daughter cells ( aneuploidy ), and conditions such as Down syndrome , if the cells survive at all. (wikidoc.org)
A telocentric chromosome's centromere is located at the terminal end of the chromosome. (wikidoc.org)
We found that particulate chromate can indeed damage chromosome structure causing chromatid lesions (Figure 2A), isochromatid lesions (Figure 2B), dicentric chromosomes (Figure 2C), and centromere spreading (Figure 2D). (wiselaboratory.org)

During early prophase the broken chromosome undergoes normal replication, but during metaphase the broken ends can fuse leading to the formation of a dicentric chromosome and an acentric fragment. (wikipedia.org)
It was shown that de may induce chromatid breaks at the Ds locus that are followed by fusions of broken ends, and that these fusions may result in the formation of a dicentric chromatid and a U-shaped acentric fragment. (nih.gov)

Lung cancer exhibits a type of genomic instability called chromosome instability, which is characterized by changes in both chromosome structure and number. (wiselaboratory.org)
Below, we present and discuss our evidence that hexavalent chromium induces genomic instability which we see more specifically as chromosome instability with both numerical and structural changes in the chromosomes. (wiselaboratory.org)
Chromosome structural variation, a vital kind of somatic mutation, is involved in the process of genomic rearrangement ranging from genes to entire chromosomes, and also affects gene expression regulation. (biomedcentral.com)

If the p (short) arm is so short that is hard to observe, but still present, then the chromosome is acrocentric (The "acro-" in acrocentric refers to the Greek word for "peak. (wikidoc.org)

These five chromosomes are the site of genes encoding rRNAs. (wikidoc.org)
Changes in chromosome structure can lead to deletions of genes or rearrangements that increase the levels of some proteins and decrease others. (wiselaboratory.org)

During mitosis the centromeres can be identified in particular during the metaphase stage as a constriction at the chromosome. (wikidoc.org)
At this centromeric constriction the two mostly identical halves of the chromosome, the sister chromatids , are held together until late metaphase. (wikidoc.org)
Figure 2A shows a normal metaphase with a normal number of chromosomes, 46. (wiselaboratory.org)
Figure 2B shows a metaphase with particulate chromate-induced chromosome instability (note that there are 92 chromosomes in the picture). (wiselaboratory.org)
A) Representative picture of a normal metaphase with 46 chromosomes. (wiselaboratory.org)
B) Representative picture of a chromate-induced tetraploid metaphase with 92 chromosomes. (wiselaboratory.org)

By genetical and cytological test methods, it was possible to place this Ds locus at a position demark- ing the proximal third of the short arm of chromosome g. (nih.gov)
This event brings about a transposition of the Ds locus from one location in the chromosome com- plement to another. (nih.gov)
These events are similar in all analyzed cases, and can be summarized as follows: During a mitotic cycle a condition may be produced at the Ds locus that results in the removal from one or both chromatids of a submicro- scopic fragment of chromatin containing the Ds locus. (nih.gov)
If the spontaneous break occurs in the short arm of chromosome 9g at a position other than the Ds locus, several types of altered chromosomes g can be formed. (nih.gov)

Based on a rangefinding assay a 20h harvest time was chosen for the aberration assay with concentrations ranging from 37.5 µg/mL through 500 µg/mL. (europa.eu)

We are the first lab to demonstrate that hexavalent chromium causes chromosome instability, DNA double strand breaks and neoplastic transformation in human lung cells. (wiselaboratory.org)
Although the patterns of structural variants are different, their formation is commonly involved in the occurrence of DNA double-strand breaks (DSB) and improper repair or rejoining of broken chromosomes [ 10 ]. (biomedcentral.com)

Lepidopteran chromosomes possess a localized kinetochore plate to which the spindle microtubules attach during cell division. (wikipedia.org)
The kinetochore plates are large and cover a significant portion of the chromosome length, ensuring that more radiation-induced breaks will not lead to the loss of chromosome fragments as is typical in species with monocentric chromosomes. (wikipedia.org)
In species with large kinetochore plates, the fragments may persist for a number of mitotic cell divisions, and can even be transmitted through germ cells to the next generation. (wikipedia.org)

humans do not possess any telocentric chromosomes. (wikidoc.org)

ZER treated cultures showed the significant increase in the frequency of the chromosome aberrations and MN induction. (waocp.com)

Chromosome aberrations, including pathogenic copy number variations (CNVs) and variations of uncertain significance (VUS), were both risk factors, increasing the risk of the adverse fetal outcome by 55.9 times and 6.7 times, respectively. (bvsalud.org)

In the present study, we aimed to determine whether chromosome aberration was associated with the occurrence of VSD and evaluate the association of VSD size, location and chromosome aberration with adverse outcomes in the Chinese fetuses. (bvsalud.org)
Our study also indicated that chromosome aberration was one of risk factors for the VSD occurrence. (bvsalud.org)
Further study shows that there is an increase in both the number of metaphases with too few chromosomes (hypodiploid) and the number of metaphases with twice the number of chromosomes (tetraploid). (wiselaboratory.org)

After adjusting confounding factors by using multivariable logistic regression analyses, the association between chromosome variations and VSD occurrence was explored. (bvsalud.org)
RESULTS: Chromosome aberration was the risk factor for VSD occurrence, raising 6.5-fold chance of developing VSD. (bvsalud.org)

Chromosome aberration, peri-membranous site and large defect size of VSD were significant risk factors of adverse fetal outcome. (bvsalud.org)

If both arms are equal in length, the chromosome is said to be metacentric . (wikidoc.org)

Among these, sex chromosome aneuploidies were mainly found in pregnant women with advanced age as well as borderline risks by serological screening. (bvsalud.org)

The association between defect size, location and chromosome aberrations and adverse foetal outcomes was also investigated. (bvsalud.org)
When Ds is trans- posed from its standard position to another position in the short arm of chromosome 9, the new location may be readily de- termined. (nih.gov)

Telomeres may extend from both ends of the chromosome. (wikidoc.org)
and the mechanism of re- moval of the fragment may be a tearing process, since unsaturated ends, capable of fusion, are produced in each of the chroma- tids of chromosome g at the position where the fragment was situated. (nih.gov)

Many oncogenes that were thought to reside only on linear chromosomes have now been shown to be present in large circular extrachromosomal DNA (ecDNA) ( Figure 1 , Table 1 ). (silverchair.com)

These effects on the DNA appear primarily in the form of alterations of the DNA structure as a result of alkylations, cross-links, or formation of DNA adducts, which subsequently leads to DNA repair mechanisms. (waocp.com)

The plates also reduce the risk of lethality caused by the formation of dicentric chromosomes, acentric fragments, and other unstable aberrations. (wikipedia.org)

Our initial work determined that particulate chromate (shown in Figure 1) induced numerical chromosome instability. (wiselaboratory.org)

Following fusion, nuclear divisions begin, and a break in a chromosome can have drastic effects on the viability of the embryo as development proceeds. (wikipedia.org)
Robertsonian -- fusion of 2 p arms by centric fusion to form metacentric chromosome. (wikidoc.org)

Anatomy67

Organisms5

Diseases31

Chemicals and Drugs39

Analytical, Diagnostic and Therapeutic Techniques and Equipment27

Psychiatry and Psychology1

Phenomena and Processes154

Disciplines and Occupations2

Anthropology, Education, Sociology and Social Phenomena1

Information Science4

Health Care9

Geographicals2

Chromosomal aberration2

Breakage3

Telomere1

Translocation2

Susceptibility1

Replication4

Mitotic1

Induce1

Mitosis1

Structural1

Breaks1

Substance1

Radiation2

Cell4

Cells2

Frequently1

Large1

Effects1

Chromosomal9

Centromere7

Acentric fragment2

Genomic3

Acrocentric1

Genes2

Metaphase6

Locus4

Assay1

Double strand breaks2

Kinetochore3

Humans1

Frequency1

Significance1

Study3

Occurrence2

Site1

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Found1

Location2

Ends2

Present1

Repair1

Risk1

Work1

Fusion2