Chromosome extrachromosomal. Medical search. Frequent questions

Extrachromosomal DNA (abbreviated ecDNA) is any DNA that is found off the chromosomes, either inside or outside the nucleus of a cell. (wikipedia.org)
Although extrachromosomal circular DNA (eccDNA) is found in normal eukaryotic cells, extrachromosomal DNA (ecDNA) is a distinct entity that has been identified in the nuclei of cancer cells and has been shown to carry many copies of driver oncogenes. (wikipedia.org)
SAN DIEGO--( BUSINESS WIRE )-- Boundless Bio , a next-generation precision oncology company developing innovative therapeutics directed against extrachromosomal DNA (ecDNA) in aggressive cancers, today announced plans to present at the AACR-NCI-EORTC Virtual International Conference on Molecular Targets and Cancer Therapeutics, held virtually from October 7-10, 2021. (businesswire.com)
Extrachromosomal DNA, or ecDNA, are distinct circular units of DNA lacking centromeres but containing functional genes, including oncogenes, that are separated from tumor cell chromosomes. (businesswire.com)
Boundless Bio is a next-generation precision oncology company interrogating a novel area of cancer biology, extrachromosomal DNA (ecDNA), to deliver transformative therapies to patients with previously intractable cancers. (businesswire.com)
Some of the DNA in cancer cells may be found in circular structures, rings of extrachromosomal DNA, or ecDNA, that may unloose all manner of mayhem. (genengnews.com)
Quantitative assessment of the chromatin state reveals that although ecDNA is packaged into chromatin with intact domain structure, it lacks higher-order compaction that is typical of chromosomes and displays significantly enhanced chromatin accessibility," the article's authors wrote. (genengnews.com)
We used the resulting dataset to show that somatic driver alterations including single-nucleotide variants, focal DNA alterations and oncogene amplification on extrachromosomal DNA (ecDNA) elements were in majority propagated from tumor to model systems. (amsterdamumc.org)
The circles, known as extrachromosomal DNA, or ecDNA, had been dismissed for decades by mainstream geneticists as a biological fluke. (stanford.edu)

In prokaryotes, nonviral extrachromosomal DNA is primarily found in plasmids, whereas, in eukaryotes extrachromosomal DNA is primarily found in organelles. (wikipedia.org)
Extrachromosomal DNA exists in prokaryotes outside the nucleoid region as circular or linear plasmids. (wikipedia.org)
Bacterial plasmids are typically short sequences, consisting of 1 to a few hundred kilobase (kb) segments, and contain an origin of replication which allows the plasmid to replicate independently of the bacterial chromosome. (wikipedia.org)
Some of the plasmids that end up in the exclusome originate from outside the cell, while others - known as telomeric rings - come from the capped ends of chromosomes, the telomeres. (myscience.ch)
Plasmids that can't be separated off could theoretically embed themselves in the chromosomes. (myscience.ch)
There are a few prokaryotes, bacteria for instance, and a few eukaryotes that have extrachromosomal DNA called plasmids. (mometrix.com)
[12] It also has two circular, extrachromosomal, double-stranded DNA plasmids, pXO1 and pXO2. (wikidoc.org)
Alphaproteobacteria are sometimes characterised by a multipartite genome group with a chromosome, secure chromids and accent plasmids. (icn2018.com)
Lateral gene transfers resulted in different linkages between the ospC gene and loci of the chromosome or other plasmids. (cdc.gov)

all genes associated with this syndrome (ie, DKC1 , TERT, TERC, NOP10 ) encode proteins in the telomerase complex responsible for maintaining telomeres at the ends of chromosomes regarding shortening length, protection, and replication. (medscape.com)

The maintenance of a single centromere per chromosome is critical for establishing bipolar microtubule attachments to the mitotic spindle and achieving high-fidelity genome segregation 17 . (nature.com)
Most DNA in an individual genome is found in chromosomes contained in the nucleus. (wikipedia.org)
Because researchers use different approaches to genome annotation , their predictions of the number of genes on each chromosome varies (for technical details, see gene prediction ). (wikipedia.org)
With a 30% difference between humans and chimpanzees, the Y chromosome is one of the fastest-evolving parts of the human genome . (iiab.me)
Chang describes the circles as vicious gangs that terrorize the chromosome-bound genome by ignoring all the understood rules of biology, making cancer therapies for some patients a game of whack-a-mole as tumors evolve drug resistance within days or weeks. (stanford.edu)
Instead, genome biologists focused on mapping the locations of and, later, sequencing individual genes on each of the 23 pairs of chromosomes in each mammalian cell. (stanford.edu)
Eukaryotic genome consists of long linear chromosomes. (irb.hr)
It mostly consists of non-coding DNA of various repeats, often prone to recombination including creation of extrachromosomal DNA which can be re-integrated into distant parts of the genome, often in different chromosome. (irb.hr)
They serve as guardians of genome stability but they also have dynamic features playing important role in cell aging and immortalization, both as chromosomal components or as extrachromosomal DNA. (irb.hr)
The 5,689,389-bp genome sequence consists of one chromosome and several extrachromosomal elements. (ncl.ac.uk)

In the study , published Nov. 30 in the online journal PLOS ONE, the mice had an extra copy of mouse chromosome 16, which has mouse counterparts to 55 percent of the genes on human chromosome 21. (edweek.org)
The following is a partial list of genes on human chromosome 9. (wikipedia.org)

In the new study, researchers identified a mechanism by which cells develop the genetic changes, known as extrachromosomal DNAs (ecDNAs) and complex genomic rearrangements, needed to acquire resistance to targeted drugs. (cancer.gov)

Double minute chromosomes (dmins) are a form of gene amplification presenting as small spherical paired chromatin bodies. (hindawi.com)
The current study attempts to demonstrate the existence of double minute chromosomes via FLT3 gene amplification in a patient diagnosed with chronic myelomonocytic leukemia (CMML). (hindawi.com)
This case study reports a rare double minute chromosome via FLT3 amplification in CMML by using array-based comparative genomic hybridization and fluorescence in situ hybridization analyses. (hindawi.com)
Double minute chromosomes (dmins) are cytogenetic indicators of extrachromosomal gene amplification which usually act as small spherical paired chromatin particles [ 1 ]. (hindawi.com)
Co-amplification of PGAP3 and ERBB2 accompanied with co-overexpression was observed in a haploid chromosome 17 of NCI-N87 cells with double minutes (DMs). (bvsalud.org)

In this scanning electron micrograph of inside the nucleus of a cancer cell, chromosomes are indicated by blue arrows and circular extrachromosomal DNA are indicated by orange arrows. (genengnews.com)

During chromothripsis, bits of DNA can drop out of chromosomes and become restitched into stand-alone circular molecules called extrachromsomal DNAs, or ecDNAs. (cancer.gov)
Together, these approaches uncovered almost 5,700 small extrachromosomal circular DNAs per tumor, on average, and an average of 0.82 large, copy number-amplified extrachromosomal circular DNA sequences, the authors reported, noting that "DNA circularization is not restricted to proto-oncogenes, but also affects various coding and non-coding regions with yet unknown functional consequences. (genomeweb.com)
Extrachromosomal DNAs (ecDNAs), also known as double minutes (DMs), can induce a fast increase in gene copy numbers and promote the development of cancer, including drug resistance. (bvsalud.org)

NEW YORK - New research suggests circularized DNA falling outside of linear chromosomes may serve as a recurrent source of somatic rearrangements in neuroblastoma, a pediatric cancer affecting immature cells in the sympathetic nervous system. (genomeweb.com)
Telomeres are among most important repetitive sequences, located at the end of linear chromosomes. (irb.hr)

While past research has pointed to a role for circularized, extrachromosomal MYCN oncogene sequences in neuroblastoma, the team explained, the full suite and the frequency of somatic mutations involving small or large stretches of circularized extrachromosomal DNA amplifications had not been fully explored. (genomeweb.com)

In addition to DNA found outside the nucleus in cells, infection by viral genomes also provides an example of extrachromosomal DNA. (wikipedia.org)
Although prokaryotic organisms do not possess a membrane-bound nucleus like eukaryotes, they do contain a nucleoid region in which the main chromosome is found. (wikipedia.org)
Human DNA typically forms long, twisting double helices of genetic material: roughly three billion base pairs organized into 23 pairs of chromosomes miraculously squeezed into every cell nucleus, each averaging just six micrometers in diameter. (genengnews.com)
We used isolated nuclei from virus infected cells supplemented with cytoplasm, and discovered that viral replicating chromosomes could continue replication in the absence of a nucleus. (nih.gov)
This is exceptional because eukaryotic cells (cells with nuclei) usually keep most of their DNA in the cell nucleus, where it is organised into chromosomes. (myscience.ch)
Inside of eukaryotes, you can locate the chromosomes inside the nucleus. (mometrix.com)

CGH has been widely applied to detect gains and losses of DNA sequences on specific chromosomes in the study of solid tumours, 1 but has not been extensively used to study unbalanced constitutional karyotypes. (bmj.com)
It consists of a 3,899,419 bp circular chromosome with 3624 predicted coding sequences. (pacb.com)
Noteworthy, was our demonstration that although termination of DNA replication did not require specific DNA sequences, some DNA sequences did promote pausing of DNA replication forks in vivo (and DNA polymerase in vitro), and some sequences, such as thosewithin the termination region for SV40 DNA replication, did promote formation of catenated intertwines during separation of sibling chromosomes. (nih.gov)
[18] This re-estimation of the age of the therian XY system is based on the finding that sequences that are on the X chromosomes of marsupials and eutherian mammals are present on the autosomes of platypus and birds. (iiab.me)

Mitochondrial DNA is a main source of this extrachromosomal DNA in eukaryotes. (wikipedia.org)
Ability to discern the central role of the chromosome in the genetics and evolution of eukaryotes. (aber.ac.uk)
Rather than passing DNA to subsequent generations by dividing into genetically identical daughter cells-a process called mitosis, involving paired chromosomes that divide and used by all eukaryotes-cancer cells propagate somewhat like bacterial cells. (genengnews.com)

As each chromosome contains a single centromere, it remains unclear how acentric fragments derived from shattered chromosomes are inherited between daughter cells during mitosis 6 . (nature.com)
Here we tracked micronucleated chromosomes with live-cell imaging and show that acentric fragments cluster in close spatial proximity throughout mitosis for asymmetric inheritance by a single daughter cell. (nature.com)
Here we show that pulverized chromosomes from micronuclei spatially cluster throughout mitosis and identify the CIP2A-TOPBP1 complex as an essential regulator of this process. (nature.com)
All chromosomes normally appear as an amorphous blob under the microscope and only take on a well-defined shape during mitosis. (iiab.me)
It is entirely coincidental that the Y chromosome, during mitosis, has two very short branches which can look merged under the microscope and appear as the descender of a Y-shape. (iiab.me)

The nature of numerical and structural chromosome change and its relationship to fertility and aetiology of human genetic disorders. (aber.ac.uk)
Although the structural chromosome abnormalities in these cases were too small to identify the origin of the extra genomic material based on banding pattern, none of the abnormalities described by these authors can be considered to be subtle or cryptic. (bmj.com)

Extrachromosomal DNA in the cytoplasm has been found to be structurally different from nuclear DNA. (wikipedia.org)
In prokaryotes, all the DNA is a single round-shaped chromosome in the cytoplasm. (mometrix.com)

The stochastic inheritance of chromosome fragments by both newly formed daughter cells could in part contribute to the alternating DNA copy-number states that are characteristic of chromothripsis 2 . (nature.com)
This module explores how chromosomes have evolved to be proficient vehicles of inheritance, and how differences and changes in chromosome number and structure have important implications for speciation and the fitness of eukaryotic organisms. (aber.ac.uk)
Drivers and models of chromosome evolution, sex determination and breeding systems, extrachromosomal inheritance and epigenetics. (aber.ac.uk)

1. Describe the structure, function and evolution of eukaryotic chromosomes, and identify the factors governing chromosome stability and driving karyotype diversity. (aber.ac.uk)

Constitutional chromosome studies involving conventional GTG band cytogenetic analysis, however, often show unbalanced karyotypes which cannot be fully defined because the extra material is too small to have a recognisable banding pattern. (bmj.com)

Autosomal" means that the gene in question is located on one of the numbered, or non-sex, chromosomes. (genome.gov)
These are some of the gene count estimates of human chromosome 9. (wikipedia.org)
The ABO gene , which determines ABO blood type , is located on the long arm of this chromosome. (wikipedia.org)
In mammals, the Y chromosome contains the gene SRY , which by default triggers male development. (iiab.me)
In mammals, the Y chromosome contains a gene, SRY , which triggers embryonic development as a male. (iiab.me)

Mice with the extra chromosomal material treated with the peptides in the womb learned as well as mice that did not have the extra chromosome, and much faster than mice with the extra chromosome that weren't treated. (edweek.org)
For whole chromosome monosomies, the odd will only increase by 29% for every extra chromosomal monosomy. (artfertilityclinics.com)

This chromosome also contains 1,722 protein-coding genes and has a 33% Guanine-Cytosine content (GC content) (3). (kenyon.edu)

We have used comparative genomic hybridisation to analyse 19 constitutional chromosome abnormalities detected by G band analysis, including seven deletions, five supernumerary marker chromosomes, two interstitial duplications, and five chromosomes presenting with abnormal terminal banding patterns. (bmj.com)
Segmental duplications and deletions as well as whole chromosome monosomies and trisomies were registered. (artfertilityclinics.com)
Segmental duplications and whole chromosome monosomies were found to have a significant effect on developmental arrest (p = 0.0163 and p = 0.0075), while trisomies and segmental deletions had no effect on developmental arrest. (artfertilityclinics.com)

Extrachromosomal DNA is often used in research into replication because it is easy to identify and isolate. (wikipedia.org)
In 1973, I continued these studies on the replication and structure of SV40 chromosomes at Harvard Medical School where they culminated in promotion to Full Professor with tenure in 1985. (nih.gov)
Therefore, the overall goal of our work is to discover how DNA replication is regulated both in the large chromosomes of cells and in the "mini-chromosomes" of viruses and small extrachromosomal DNA molecules. (nih.gov)
In the presence of functional DNA replication, RTEL1 mutations produce a large amount of extrachromosomal T-circles. (medscape.com)

Our analysis shows that extrachromosomal elements allow rapid increase of genomic heterogeneity during GBM evolution, independently of chromosomal DNA alterations. (amsterdamumc.org)

It also shows how chromosomes provide the environment for the expression and recombination of genes, and how chromosomes underpin sex determination and the evolution of breeding systems. (aber.ac.uk)

Defining and comparing karyotypes by chromosome components. (aber.ac.uk)

Others have applied CGH to the study of constitutional chromosome abnormalities detected postnatally. (bmj.com)

Microbiologists in the mid-1960s who observed the ring-shaped structures near chromosomes called them "minutes" (with a long vowel i), meaning tiny. (stanford.edu)

In humans, aneuploidy would be any number of chromosomes other than the usual 46. (genome.gov)
fChromosome 9 is one of the 23 pairs of chromosomes in humans . (wikipedia.org)
Humans normally have two copies of this chromosome, as they normally do with all chromosomes. (wikipedia.org)
The Y chromosome is one of two sex chromosomes ( allosomes ) in mammals, including humans , and many other animals. (iiab.me)
The Y chromosomes of humans and other mammals also contain other genes needed for normal sperm production. (iiab.me)

These studies implicate a potential mechanism suppressing the loss of genetic material after chromosome pulverization, although how distinct patterns of rearrangements arise in cancer and germline disorders remains unclear. (nature.com)
It was a Tuesday afternoon in December 2017, and Paul Mischel , MD, then a cancer biologist at UC San Diego, had just finished giving a talk at Stanford describing a surprising observation: small circles of DNA in cancer cells bobbing in the cells' nuclei, untethered to nearby chromosomes - the multiple long chains of DNA that comprise the cells' genetic material. (stanford.edu)

Chromosome 9 spans about 150 million base pairs of nucleic acids (the building blocks of DNA ) and represents between 4.0 and 4.5% of the total DNA in cells . (wikipedia.org)
The DNA in the human Y chromosome is composed of about 59 million base pairs. (iiab.me)
Stevens proposed that chromosomes always existed in pairs and that the Y chromosome was the pair of the X chromosome discovered in 1890 by Hermann Henking. (iiab.me)

Thus, distinct patterns of chromothripsis can be explained by the spatial clustering of pulverized chromosomes from micronuclei. (nature.com)

This loss occurs because the cancer can either make multiple copies of defective versions of these genes, or use circular rings of DNA from outside the chromosome (called extrachromosomal DNA) to override normal copies of the genes. (htworld.co.uk)

Chromosomes carry genes with great precision and fidelity between cell cycles, and from one generation to the next. (aber.ac.uk)
Aneuploidy is an abnormality in the number of chromosomes in a cell due to loss or duplication. (genome.gov)
Most therian mammals have only one pair of sex chromosomes in each cell. (iiab.me)
Within a cell, DNA ordered into dense protein-DNA complexes are called chromosomes. (mometrix.com)

Mitotic clustering facilitates the reassembly of acentric fragments into rearranged chromosomes lacking the extensive DNA copy-number losses that are characteristic of canonical chromothripsis. (nature.com)

In contrast to most of Rhodobacterales, this strain lacks any extrachromosomal elements. (pacb.com)

The X and Y chromosomes are thought to have evolved from a pair of identical chromosomes, [11] [12] termed autosomes, when an ancestral animal developed an allelic variation, a so-called "sex locus" - simply possessing this allele caused the organism to be male. (iiab.me)

In an earlier study, Spong and her colleagues found that, if treated with neuroprotective peptides in the womb, mice with the extra copy of chromosome 16 achieved developmental milestones earlier than mice with the same condition that were not treated. (edweek.org)

Even so, the team's follow-up analyses - including RNA sequencing experiments - indicated that rearrangements stemming from extrachromosomal circular DNA from MYCN and other genes may be a recurrent and ongoing source of new mutations through a multi-hit model in neuroblastoma. (genomeweb.com)
Astyanax sp (2n = 52), in addition to variations due to heterochromatic blocks, has its origin possibly by events of centric fission in a pair of chromosomes followed by minor rearrangements.These results show an interesting karyotypic diversity in Astyanax and indicate the need of a review of the group referred as A. aff. (scielo.org)

[7] All Y-linked genes are expressed and (apart from duplicated genes) hemizygous (present on only one chromosome) except in the cases of aneuploidy such as XYY syndrome or XXYY syndrome . (iiab.me)

She realized that the previous idea of Clarence Erwin McClung, that the X chromosome determines sex, was wrong and that sex determination is, in fact, due to the presence or absence of the Y chromosome. (iiab.me)

Over five days of testing, researchers found that the time the mice spent searching for the platform dropped significantly except for the mice with the extra chromosome not treated in the womb. (edweek.org)

In particular, G band analysis usually does not show the chromosomal origin of small marker chromosomes or of a small amount of extra material detected on otherwise normal chromosomes. (bmj.com)

The results showed 2n = 50 chromosomes for five species and a karyotype with 52 chromosomes in Astyanax sp. (scielo.org)

FLT3 (FMS-related tyrosine kinase 3) located on chromosome 13q12.2 encodes a receptor tyrosine kinase (RTK) that activates the Ras and PI3 kinase pathway leading to the increased proliferation and inhibition of apoptosis in hemopoietic progenitor cells [ 7 ]. (hindawi.com)
Extra or missing chromosomes help cancer cells survive treatment, new studies shows. (cancer.gov)
It's one of the key hygiene functions cells perform to protect the chromosomes. (myscience.ch)

Multiple forms of extrachromosomal DNA exist, and, while some of these serve important biological functions, they can also play a role in diseases such as cancer. (wikipedia.org)
Howard Chang, left, and Paul Mischel are turning cancer research on its head with their discoveries about rings of DNA that exist outside of chromosomes. (stanford.edu)

Here, they display a rendering of the rings (smallest circles) mixed with chromosomes (oblongs) and nuclei (large spots). (stanford.edu)

Anatomy62

Organisms19

Diseases20

Chemicals and Drugs41

Analytical, Diagnostic and Therapeutic Techniques and Equipment27

Phenomena and Processes158

Disciplines and Occupations2

Information Science4

EcDNA9

Plasmids9

Ends of chromosomes1

Genome10

Genes on human chromosome2

Known as extrachromosomal1

Amplification5

Circular extrachromosomal1

DNAs3

Linear chromosomes2

Oncogene1

Nucleus6

Sequences4

Eukaryotes3

Mitosis5

Structural chromosome2

Cytoplasm2

Inheritance3

Eukaryotic1

Cytogenetic1

Gene5

Extra-chromosomal2

Protein-codin1

Duplications3

Replication4

Genomic1

Recombination1

Karyotypes1

Abnormalities1

Structures1

Humans5

Genetic material2

Pairs3

Distinct1

Copies1

Cell4

Chromothripsis1

Lacks1

Ancestral1

Developmental1

Rearrangements2

Aneuploidy1

Determination1

Researchers1

Small1

Species1

Cells3

Cancer2

Large1