Process of x chromosome i. Medical search. Frequent questions

Dosage compensation is the process by which organisms equalize the expression of genes between members of different biological sexes. (wikipedia.org)
Because sex chromosomes contain different numbers of genes, different species of organisms have developed different mechanisms to cope with this inequality. (wikipedia.org)
Thus, human females have the same number of expressed X-linked genes per cell as do human males (XY), both sexes having essentially one X chromosome per cell, from which to transcribe and express genes. (wikipedia.org)
Some lineages have evolved dosage compensation, an epigenetic mechanism which restores expression of X or Z specific genes in the heterogametic sex to the same levels observed in the ancestor prior to the evolution of the sex chromosome. (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)
The following is a partial list of genes on human chromosome 9. (wikipedia.org)
The report notes that the gene, eed, when functioning normally in female mouse embryos, keeps the paternal X chromosome inactive and many of its genes shut down in early placental cells. (sciencedaily.com)
As female mammals have two X chromosomes (XX) and males an X and Y (XY), imbalance occurs because female embryos have twice as many X-linked genes. (sciencedaily.com)
When that happens, too many X chromosome genes are active, there are problems forming placental tissue, and female embryos die. (sciencedaily.com)
The potential power of genes or the tendency of genes on chromosomes to stay together even after crossing over or heredity transmission is called linkage. (gkscientist.com)
The reason is that the genes of red-eye colour and grey-body colour lie in the same chromosome and, therefore, go together in the gamete and the next generation. (gkscientist.com)
The genes lie in linear order in the chromosome. (gkscientist.com)
The genes that show the phenomenon of linkage are situated in the same chromosome. (gkscientist.com)
Complete Linkage- The genes closely located in the chromosome show complete linkage as they have no chance of separating by crossing over and are always transmitted together to the same gamete and the same offspring. (gkscientist.com)
Incomplete Linkage- The genes distantly located in the chromosome show incomplete linkage because they have a chance of separation by crossing over and of going into different gametes and offspring. (gkscientist.com)
Linked Genes- The genes which are present on the same chromosome are called linked genes. (gkscientist.com)
Unlinked Genes- These genes are present on another chromosome of the same pair and these are unable to show linkage but however, during mutation some genes are deleted and are set close to linked genes. (gkscientist.com)
It refers to the total number of genes present on the chromosomes. (gkscientist.com)
For example- In a human male X chromosome of the 23rd pair has 102 genes so it forms a large linkage group whereas the Y chromosome has only 10 genes hence it forms a small linkage group. (gkscientist.com)
In order to ensure the proper expression level of genes on the X chromosome, one of the chromosomes is randomly inactivated in every cell in a female mammal. (drugdiscoverynews.com)
XIST attaches itself at different points all along the X chromosome, silencing the genes that are located on the X chromosome," said senior author Dr. Samie Jaffrey, a professor of pharmacology at Weill Cornell Medicine. (drugdiscoverynews.com)
Understanding how X chromosome inactivation occurs may enable researchers to develop therapies for a variety of diseases caused by mutations of genes on the X chromosome. (drugdiscoverynews.com)
But SCDC mechanisms work to upregulate, or increase the level, of protein production from genes in the single Z (or X) chromosomes. (newswise.com)
The researchers then compared the activity of genes from sex chromosomes and from autosomes, broken down by male and female turtles. (newswise.com)
The decondensing (loosening) and swelling of the chromosomal sites of hormone-responsive genes on polytene chromosomes in response to increased production of the steroid hormone 20-hydroxyecdysone (ecdysone) in Drosophila larvae approaching pupation. (yeastrc.org)
The signs and symptoms of Wolf-Hirschhorn are related to the loss of multiple genes on the short arm of chromosome 4. (medlineplus.gov)
Scientists are working to identify additional genes at the end of the short arm of chromosome 4 that contribute to the characteristic features of Wolf-Hirschhorn syndrome. (medlineplus.gov)
In previous research (Nature, July 2013), UC Berkeley scientists Beatriz Vicoso, Ph.D., and Doris Bachtrog, Ph.D., determined that genes on the so-called "dot chromosome," or fourth chromosome, of the fruit fly Drosophilia melanogaster are X-linked in three other related fly species. (phys.org)
For example, the expression levels of genes on the "dot chromosome" generally are higher in female than in male fly embryos during early development. (phys.org)
The human Y chromosome has retained only 3% of its ancestral genes. (theconversation.com)
The Y chromosome, that little chain of genes that determines the sex of humans, is not as tough as you might think. (theconversation.com)
The Y is a small chromosome with not more than 70 coding genes, in contrast to the X chromosome harbours more than 1000 genes. (erasmusmc.nl)
In mammals this involves upregulation of dosage sensitive X-linked genes, and inactivation of one X chromosome in every female somatic cell. (erasmusmc.nl)
As a tool to understand one part of RNA's regulation of genes, Yildirim's lab is focused on the process that silences one of the two X chromosomes found in a female mammal. (duke.edu)
Female offspring get one X from each parent, but if the genes on both chromosomes were active, all sorts of things could go wrong. (duke.edu)
According to a hypothesis called «gene dosage disequilibrium», the presence of a third chromosome 21 could influence the expression of all the other genes in the genome. (unige.ch)
That is, this extra genetic material could disrupt the process through which information carried in the genes is decoded, therefore modifying the cellular function. (unige.ch)
The researchers noticed that the expression of genes located on all the other chromosomes (outside of chromosome 21) were disturbed in trisomic cells. (unige.ch)
Generally speaking, chromosomes are divided into domains that contain genes with rather similar levels of RNA production. (unige.ch)
Overview of Chromosome and Gene Disorders Chromosomes are structures within cells that contain a person's genes. (msdmanuals.com)
eling require a broad range of signal processing approaches, Two salient goals of functional genomics are to screen for including signal representation relevant to transcription and key genes and gene combinations that explain specific cel- system modeling using nonlinear dynamical systems. (lu.se)
The continuously updated material also makes it possible to address scientific questions related to the mechanisms through which chromosomal/genomic changes participate in the carcinogenic process by elucidating why, how and when chromosome abnormalities are formed, the chromosomal anatomy of cytogenetic changes and genes involved in fusions, the role chromosome aberrations play in the formation of fusion genes, and the mechanisms by which gene fusions exert their effects. (lu.se)
Genes Chromosomes Cancer 58:149-154, 2019. (lu.se)
Genes Chromosomes Cancer 55:291-310, 2016. (lu.se)

An aberration in which an extra chromosome or a chromosomal segment is made. (harvard.edu)
An extra chromosome 21 leads to trisomy, also known as Down syndrome. (gizmodo.com)
Ideally, if you were to create an extra chromosome, rather than putting extra genetic material and inserting it into an existing chromosome - where it might be put into a random spot or put into something else that's going on - you have a very controlled environment," he told io9. (gizmodo.com)
A study conducted by Stylianos Antonarakis and his team in the Department of Genetic Medicine and Development at the University of Geneva (UNIGE) Faculty of Medicine, published in Nature , shed light on how the extra chromosome 21 upsets the equilibrium of the entire genome, causing a wide variety of pathologies. (unige.ch)
At UNIGE, Stylianos Antonarakis's team has the unique opportunity to examine the genomes of two identical twins with the exact same genetic makeup, except for an extra chromosome 21 present in one of them. (unige.ch)
Down syndrome is a chromosome disorder caused by an extra chromosome 21 that results in intellectual disability and physical abnormalities. (msdmanuals.com)
Down syndrome is caused by an extra chromosome 21. (msdmanuals.com)
After birth, the diagnosis is suggested by the child's physical appearance and is confirmed by finding an extra chromosome 21, usually by testing a blood sample. (msdmanuals.com)

The Database of Chromosome Aberrations and Gene Fusions in Cancer, established in 1980, is an attempt to register systematically all published cytogenetic aberrations reported in cancer, including patient and tumor characteristics, gene fusions identified by cytogenetics or massively parallel sequencing, and studies pertaining to the clinical relevance of cytogenetic aberrations and/or gene rearrangements. (lu.se)

Building on work done by Ohno and his colleagues, Lyon eventually proved that either the maternal or paternal X chromosome is randomly inactivated in every cell of the female body in the species she was studying, which explained the heterogeneous fur patterns she observed in her mosaic mice. (wikipedia.org)

In order to neutralize the large difference in gene dosage produced by differing numbers of sex chromosomes among the sexes, various evolutionary branches have acquired various methods to equalize gene expression among the sexes. (wikipedia.org)
Different lineages have evolved different mechanisms to cope with the differences in gene copy numbers between the sexes that are observed on sex chromosomes. (wikipedia.org)
One logical way to equalize gene expression amongst males and females that follow a XX/XY sex differentiation scheme would be to decrease or altogether eliminate the expression of one of the X chromosomes in an XX, or female, homogametic individual, such that both males and females then express only one X chromosome. (wikipedia.org)
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)
We show that although the nascent Y chromosome encompasses nearly half of the linkage group, there has been no perceptible degradation of Y chromosome gene content or activity. (nature.com)
The dominant theoretical model for the early stages of sex chromosome evolution 3 , 4 , 5 predicts that recombination will be selected against in the region between a sex determining gene and a nearby locus with alleles of sex-specific effect. (nature.com)
A study authored by UNC researchers and published in the August issue of "Nature Genetics" furthers the understanding of a fundamental biological process in mammals and contributes important new knowledge to gene regulation in the developing embryo. (sciencedaily.com)
Other studies have shown that the gene Xist is responsible for putting the molecular brakes only on the X chromosome. (sciencedaily.com)
This gene is activated from the X chromosome that's going to be shut down, which in early placental material is only the X from the father, according to Terry Magnuson, PhD, senior author of the new study and Kenan professor of genetics at UNC-CH School of Medicine. (sciencedaily.com)
The new findings also suggest that eed may be critical in a fundamental process known as imprinting, a phenomenon in which a specific gene is expressed, or turned on, depending on whether it is inherited from the mother or the father. (sciencedaily.com)
We hope to block methylation of XIST in order to restore gene expression in Rett syndrome and similar genetic diseases in females carried on the X chromosome. (drugdiscoverynews.com)
The Z chromosomes contain instructions for some of the proteins normally functioning cells should produce, and having only a single copy of a chromosome can result in a reduced amount of proteins produced, because protein production is often affected by the number of gene copies. (newswise.com)
The resulting degradation of the Y chromosome gene content creates the need for dosage compensation in the heterogametic sex. (uncommondescent.com)
They identified nine independently evolved sex chromosomes in a wider variety of fly species than had previously been examined and determined that these newly formed X-chromosomes have become dosage compensated, to balance the relative gene expression between males and females. (phys.org)
Many animal species employ sex chromosomes to determine sex and start gender specific gene expression programs. (erasmusmc.nl)
The SP-B gene is on human chromosome 2, and its primary translation product is 40 kd, which is clipped to become an 8-kd protein in the type II cells before entering lamellar bodies to be cosecreted with phospholipids. (medscape.com)
EURASIP Journal on Applied Signal Processing dynamical modelling of gene networks. (lu.se)
Mitelman F, Johansson B, Mertens F, Schyman T, Mandahl N. Cancer chromosome breakpoints cluster in gene-rich genomic regions. (lu.se)

Across species, different sexes are often characterized by different types and numbers of sex chromosomes. (wikipedia.org)
The importance of maintaining a proper balance is made evident by diseases caused by abnormal numbers of sex chromosomes, including Klinefelter syndrome and Turner syndrome in humans, and Valenzuela said these processes have evolutionary and health implications in many other organisms as well. (newswise.com)

These chromosomes also contain the genetic codes for the production of essential proteins, and the disproportion in chromosomes in XY individuals caused by them carrying only a single X for every pair of non-sex chromosomes (called autosomes) can lead to an imbalance in the production of proteins. (newswise.com)
Classic theory predicts that sex chromosomes originate from a pair of homologous autosomes and recombination between them is suppressed via inversions to resolve sexual conflict. (uncommondescent.com)
For example, it is clear that sex chromosome pairs are not always derived from homologous autosomes. (uncommondescent.com)
So once again, lets see who believes in miracles: "Sex chromosomes are derived from autosomes and have evolved independently many times in different lineages. (uncommondescent.com)
At the GSA Drosophila Research Conference, scientists will present evidence of many reversals of sex chromosome to autosomes in flies. (phys.org)
This meant that males could have matching autosomes and Y chromosome with a mismatched X, or matching autosomes and X chromosome with a mismatched Y. For this specific experiment we picked eight of the novel genotypes, which have previously been shown to exhibit phenotypic differences, as well as their corresponding wild type populations for RNA pooled sequencing. (lu.se)

Despite many convergent genomic patterns exhibited by independently evolved sex chromosome systems, and many case studies supporting these theoretical predictions, emerging data provide numerous interesting exceptions to these long-standing theories, and suggest that the remarkable diversity of sex chromosomes is matched by a similar diversity in their evolution. (uncommondescent.com)

This X-shape arrangement of chromosomes is required to ensure that each of the two daughter cells receive an identical copy of the genome. (le.ac.uk)
A . Schematic of the bouquet configuration of chromosomes during meiotic prophase I. The spatial arrangement of chromosomes with telomeres clustered and attached at the inner nuclear membrane is shown. (biorxiv.org)

The cell cycle process in which replicated homologous chromosomes are organized and then physically separated and apportioned to two sets during the first division of the meiotic cell cycle. (yeastgenome.org)
Prior to the first meiotic division, homologous chromosomes pair, synapse, and recombine to ensure their proper disjunction at anaphase I. Additionally, telomeres tethered at the nuclear envelope cluster in the bouquet configuration where they are subjected to dramatic pulling forces acting from outside of the nucleus. (biorxiv.org)

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)
Pentasomy X is a rare disorder of the sex chromosomes, which only affects females and is characterized by the presence of five chromosomes "x" (49,xxxxx) instead of two (46,xx). (bvsalud.org)

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)
By comparing their results with data previously published by other research groups, UNIGE researchers noticed that this specific chromosomes organization correlates with DNA position in the cell nucleus. (unige.ch)

Others have applied CGH to the study of constitutional chromosome abnormalities detected postnatally. (bmj.com)
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)
Although JTs have been reported in neoplasms and constitutional chromosome abnormalities, they are rare chromosome rearrangements in neoplastic diseases. (biomedcentral.com)

Chromosome segregation errors during meiosis are the leading cause of birth defects and developmental delays in humans ( H assold and H unt 2001 ). (biorxiv.org)
Chromosome axis organization is complex during meiosis, when DNA repair needs to be coordinated with homology searching and synapsis. (bham.ac.uk)
For the first time, we report that TOPII and chromosome movement collaborate in interlock resolution during meiosis, confirming predictions from decades ago. (bham.ac.uk)

Ohno's studies of Barr bodies in female mammals with multiple X chromosomes revealed that such females used Barr bodies to inactivate all but one of their X chromosomes. (wikipedia.org)
NEW YORK-The addition of a chemical tag on an RNA molecule is the critical switch that inactivates one X chromosome in every cell, ensuring healthy development in all female mammals, according to new research by Weill Cornell Medicine investigators. (drugdiscoverynews.com)
All cells in female mammals contain two X chromosomes, but only one is needed for proper cell function and development, Weill Cornell notes. (drugdiscoverynews.com)
In mammals female cells have two X chromosomes, whereas male cells carry an X and Y chromosome. (erasmusmc.nl)

It may also be defined as the haploid number of chromosomes in a particular species. (gkscientist.com)
The study looks at a species of softshell turtle, but the results could help to illuminate an important evolutionary process in many species, said Nicole Valenzuela, professor of ecology, evolution and organismal biology and lead author of the study. (newswise.com)
For instance, in humans and many other species, sex chromosomes are referred to as X and Y. Typically, two X chromosomes result in a female while XY chromosomes result in males. (newswise.com)
In the case of the softshell turtles included in the study, the sex chromosomes are referred to as Z and W, and it's the females of the species who have mismatched, or ZW, chromosomes. (newswise.com)
Valenzuela has studied temperature-dependent sex determination (TSD), or the way environmental temperatures influence whether a turtle embryo develops into a male or female in species that lack sex chromosomes, in previous research. (newswise.com)
Chromosome number could be but is not considered a defining attribute of a taxonomic species. (carnivorousplants.org)
Chromosome number is not an effective feature in the definition of biological species either although differences in chromosome number can produce different biological species. (carnivorousplants.org)
In spite of our lack of attention to chromosomes and chromosome numbers in formally defining species, it is the chromosomes and the genetic material they contain that define true species and control the evolution of new species. (carnivorousplants.org)
Drosera can have anywhere from 8 to 80 chromosomes depending on the species. (carnivorousplants.org)
There are two factors related to chromosomes and species that work separately and together to make life interesting. (carnivorousplants.org)
This process is totally independent of taxonomic characters used to define species. (carnivorousplants.org)
The more similar the chromosomes (the genome and epigenome as well as chromosome number) the more likely hybrids will form and reproduce but also the more likely the net result will only be the introgression of genetic material from one species to the other. (carnivorousplants.org)
Abstract Genomic analysis of many non-model species has uncovered an incredible diversity of sex chromosome systems, making it possible to empirically test the rich body of evolutionary theory that describes each stage of sex chromosome evolution. (uncommondescent.com)
as mentioned in the article above, sex chromosomes evolved multiple times, independently in various species ( by random unguided natural process) i am sure, that very few lay people even know, that this is what scientists seriously claim in their evolutionary theory. (uncommondescent.com)
The human Y chromosome could disappear over time, putting our species in jeopardy. (theconversation.com)
But the researchers say their findings shed light on the evolutionary role of sex chromosome dosage compensation in many species. (scitechdaily.com)
Highly differentiated sex chromosomes are common in many species. (lu.se)

A process of chromosome organization that is involved in a meiotic cell cycle. (mcw.edu)

this is called X-inactivation), a two-fold increase in the transcription of a single male X chromosome (as observed in Drosophila melanogaster), and decreased transcription by half in both of the X chromosomes of a hermaphroditic organism (as observed in Caenorhabditis elegans). (wikipedia.org)
Drosophila has 8 chromosomes and its linkage group is 4. (gkscientist.com)
We have previously found empirical evidence for antagonistic coevolution between the sex chromosomes in Drosophila melanogaster (see Lund-Hansen et al 2021, https://www.pnas.org/doi/full/10.1073/pnas.2003359118 ) and are now interested in determining how expression is altered in males with mis-matched sex chromosomes. (lu.se)

The process of X chromosome inactivation is triggered by an RNA called XIST. (drugdiscoverynews.com)
XIST is a long RNA that attaches to the X chromosome to initiate X inactivation. (drugdiscoverynews.com)
These act as docking sites to recruit proteins that initiate a cascade of events leading to X chromosome inactivation. (drugdiscoverynews.com)
They found that cells that could not methylate XIST were not able to carry out X chromosome inactivation. (drugdiscoverynews.com)
X chromosome inactivation (XCI) is regulated by the X-linked X inactivation centre (Xic). (erasmusmc.nl)

Analysis of the first TOPII mutants described in plants also revealed a link with HR. Chromosome replication, condensation and segregation phenotypes were consistent with previous studies of TOPII in other organisms. (bham.ac.uk)

Large chromosome forms large linkage group whereas small chromosome forms small linkage group. (gkscientist.com)

Once the paternal X chromosome is shut down, then the cells must continue to divide and keep it shut down. (sciencedaily.com)
However, this occurs randomly since about 50 percent of the time either the paternal or a maternal X chromosome is shut down. (sciencedaily.com)
They occur when sections of the maternal and paternal versions of chromosomes overlap and connect. (fredhutch.org)
Crossovers are formed when the broken end of a maternal chromosome links up with the broken end of its paternal counterpart. (fredhutch.org)
This also allows maternal and paternal chromosomes to increase genetic diversity by swapping large segments. (fredhutch.org)

The researchers also found a protein, called DC1, that binds to every methyl group on XIST and enables it suppress the X chromosome. (drugdiscoverynews.com)
Now, researchers in New York have shown what shelterin protects chromosomes from-six different DNA repair systems, including two not previously known to attack telomeres. (the-scientist.com)
If the researchers inserted into a chromosome a new DSB hotspot close to other hotspots, the frequency of DSBs at those other hotspots dropped. (fredhutch.org)
Now, a team of researchers led by Professor Daniel Panne at the University of Leicester and Dr Benjamin Rowland at the Netherlands Cancer Institute have determined at a molecular level how the iconic X-shape of chromosomes is generated during cell division. (le.ac.uk)

once an X chromosome is inactivated, it stays inactive throughout the lifetime of the organism. (drugdiscoverynews.com)
Chromosomes are packages of the genetic material located in our cells - the foundation of our basic biology as an organism. (gizmodo.com)

The most common trisomy in a newborn is trisomy 21 (three copies of chromosome 21, which is the smallest human chromosome). (msdmanuals.com)

For decades, scientists have known that chromosomes are protected by repetitive DNA known as telomeres, which themselves are protected by a cap of six proteins called shelterin. (the-scientist.com)
There aren't four pathways, but six, that pose a threat to the integrity of the chromosome end, and that telomeres must protect against. (the-scientist.com)
Shortened or damaged telomeres are a hallmark of the cellular aging process, as well as many diseases including cancers and dyskeratosis congenita, an inherited disorder that causes premature aging. (the-scientist.com)
Telomeres are structures at the ends of chromosomes that contain repetitive stretches of DNA. (cdc.gov)

Although we have a detailed understanding of the evolutionary consequences of the loss of recombination for sex chromosome evolution 1 , 2 , we still do not understand the evolutionary forces acting to halt recombination in the first place. (nature.com)
We are looking for a student with bioinformatic skills, who also have good understanding and interest in evolutionary processes. (lu.se)

Sex- The sex having heteromorphic chromosomes has stronger linkage groups as compared to the other sex. (gkscientist.com)
It is difficult to study these processes in old, already highly heteromorphic, sex chromosomes. (lu.se)

XXYY syndrome happens when males have an extra X and Y chromosome, leading to developmental delays, extra height, and learning disabilities. (gizmodo.com)
Drs. Bachtrog and Vicoso also found evidence of female-biased expression of these chromosomes in the gonads, as expected if sexual antagonism in the form of opposing selective pressures in males versus females played an important role in shaping the expression of this chromosome. (phys.org)

Certain chromosomes may be put in place to serve as a backup, or to function at a specific stage of a person's life (such as during elderly years when existing genetics isn't up to the task). (gizmodo.com)
The research group Genetics of Sex Differences is interested in sexual selection and sexual conflict, the evolution of sexual dimorphism, and sex chromosome evolution. (lu.se)

SMC5/6 is required for replication fork stability and faithful chromosome segregation during neurogenesis. (nih.gov)
Telomeric sequences at the ends of chromosomes protect the coding DNA from erosion during DNA replication . (the-scientist.com)
The events of meiotic prophase follow a specialized round of DNA replication when the meiotic chromosome axis is formed. (biorxiv.org)
In addition to non-homologous end joining, we detect signatures of replication-associated processes and templated insertions. (lu.se)

To cap- lular phenotypes (e.g. disease) on a mechanistic level, and ture the complex network of nonlinear information process- to use genomic signals to classify disease on a molecular ing based upon multivariate inputs from inside and outside level. (lu.se)
Genomic signal processing (GSP) is the discipline that studied and developed--in particular, estimation, classifi- studies the processing of genomic signals. (lu.se)
More- ing with the global understanding of functional genomics, over, signal processing is based on a holistic view of regu- with special emphasis on genomic regulation. (lu.se)

Abstract: "Frequent sex chromosome transitions in Dipterans. (phys.org)

Karyotype was abnormal, with unbalanced 1q JTs to the short arms of acrocentric chromosomes 14 and 21, leading to gain of 1q. (biomedcentral.com)
these abnormal chromosomes are often observed in cancer cells. (cdc.gov)

Fusion of the break-off donor chromosome segment to telomeric or interstitial regions of recipient chromosomes can form different chromosomal patterns of jumping translocations. (biomedcentral.com)

JTs are characterized by translocations of one donor chromosome to various recipient chromosomes, resulting in several gains of this chromosomal segment and possible loss of segments of the recipient chromosomes [ 1 , 2 ]. (biomedcentral.com)

Scientists at Fred Hutchinson Cancer Research Center have worked out the molecular underpinnings of how chromosomes make the right number of crossovers - important links that make it possible for developing sex cells (eggs or sperm in humans) to sort those chromosomes properly. (fredhutch.org)
In work published today in the Proceedings of the National Academy of Sciences, Hutch molecular biologist Dr. Gerry Smith and his team outline just such a model in yeast that explains how chromosomes find their happy medium during sex-cell formation. (fredhutch.org)
Professor Panne said: "It is exciting to finally understand at a molecular and atomic level how the iconic X-shape of chromosomes during cell division is generated. (le.ac.uk)
Chromosomal identification of marker chromosomes and extra bands on chromosomes through molecular techniques is always of clinical interest. (bmj.com)
On these bases, the aim of the Research Topic entitled "Inflammation and Aging in Chronic and Degenerative Diseases: Current and Future Therapeutic Strategies" was to collect the latest update on the molecular and cellular determinants responsible for inflammatory processes during aging as well as the role of aging in the onset of chronic-degenerative diseases. (researchgate.net)
SP-A is an innate host defense, large molecular, hydrophilic (water soluble) lectin coded on human chromosome 10 that regulates lung inflammation. (medscape.com)

Thus, Ohno described the "n-1" rule to predict the number of Barr bodies in a female with n number of X chromosomes in her karyotype. (wikipedia.org)

Sex chromosomes evolve once recombination is halted between a homologous pair of chromosomes. (nature.com)
Sex chromosomes are typically thought to evolve as recombination is halted between a homologous pair of chromosomes in one sex. (nature.com)
Many organisms determine their sex by a pair of specialized chromosomes that appear in virtually every cell of an organism's body. (newswise.com)
A matched pair of chromosomes results in one sex, while a mismatched pair results in another sex. (newswise.com)
Normally, an extra pair of chromosomes would be considered dangerous. (gizmodo.com)
Here's how a 24th pair of chromosomes could change our biologies forever. (gizmodo.com)
Another advantage is that if you preprocess with AS-CRMAv2 and BAF normalize with TumorBoost you have a truly single-pair processing method, i.e. you can process your tumor-normal pairs one by one independently of all other pairs you have. (mail-archive.com)

Also, both the cause and mechanism of recombination suppression between sex chromosome pairs remain unclear, and it may be that the spread of recombination suppression is a more gradual process than previously thought. (uncommondescent.com)

In many cases, women with these diseases have one normal and one mutated X chromosome, but it is the normal chromosome that has been suppressed. (drugdiscoverynews.com)
2021). Of note, inflammation and aging are both pathophysiological processes that have been associated with an increased risk of different chronic-degenerative diseases, including tumors, neurological and cardiovascular disorders (Gupta et al. (researchgate.net)
2021). Besides these well-known pathogenetic mechanisms related to inflammaging, other processes are involved in age-related and inflammatory-related diseases including enzyme dysfunctions, cell death, impaired tissue renewal and tissue degeneration (Li, 2013). (researchgate.net)
Telomere shortening and chronic diseases could be caused by the same cell-damaging processes, such as oxidative stress and inflammation. (cdc.gov)

In order to trace the origins and migratory patterns that may have led to the genetic isolation and autosomal clustering in some of these communities we analyzed Y-chromosome STR and SNP sample data from 6327 individuals, in addition to whole genome autosomal sample data from 609 individuals, from Mount Lebanon and other surrounding communities. (nature.com)
There are two types: autosomal and sex chromosomes. (gizmodo.com)

These results provide empirical support for longstanding models of sex chromosome catalysis, and suggest an important role for sexual selection and sexual conflict in genome evolution. (nature.com)
These findings show that chromothripsis is a major process that drives genome evolution in human cancer. (lu.se)

and protein localization to chromosome, centromeric region. (nih.gov)
This whole package of DNA (genome) and protein (epigenome) in a chromosome is what controls the development and maintenance of eukaryotic organisms (protists, fungi, animals, and plants). (carnivorousplants.org)
The team studied a key component of a ring-shaped protein complex called cohesin that is known to be important for holding chromosomes together during cell division. (le.ac.uk)
its primary translation product, 22 kd, is processed to an extremely hydrophobic 4-kd protein that is associated with lipids in lamellar bodies. (medscape.com)

But the research could help scientists understand the process in other organisms as well. (newswise.com)
Ever since the invention of the first light microscopes more than 100 years ago, scientists have puzzled over how chromosomes receive their X-shape during cell division. (le.ac.uk)
This has not only intrigued generations of scientists but is also important for our understanding of how this process can go wrong in disease. (le.ac.uk)
1. Cloning is an umbrella term traditionally used by scientists to describe different processes for duplicating biological material. (who.int)

Among the many vital steps, genetic material packaged in chromosomes - half from mom and half from dad - must be faithfully copied and precisely parceled out to the new cells. (fredhutch.org)
These connections create tension that helps chromosomes properly pull apart as the cell divides, ensuring each new cell ends up with exactly the right set of genetic material. (fredhutch.org)

Using replicate wild populations with differing levels of sexually antagonistic selection for colour, we also show that sexual selection leads to greater expansion of the non-recombining region and increased Y chromosome divergence. (nature.com)
To investigate the antagonistic coevolution between the sex chromosomes, we carried out a round robin crossing scheme, where we swapped either the X or the Y chromosome between five populations of D. melanogaster stemming from different places in the world. (lu.se)
We therefore attempt to study the early evolution of sex chromosomes using a variety of methods, including characterization of new portions of the sex chromosome in natural populations, and experimental evolution of sex chromosomes in the lab. (lu.se)

The process of X chromosome suppression is a cascade. (drugdiscoverynews.com)

If this process goes wrong and the genome is not evenly distributed this can lead to cancer or to trisomies such as Down Syndrome. (le.ac.uk)
Pentasomy of the x chromosome is a rare syndrome of unknown incidence and there are few reports in the scientific literature, especially in terms of dental care for patients with this syndrome. (bvsalud.org)

Then, in 1959 Susumu Ohno proved that these satellite-like structures found exclusively in female cells were actually derived from female X chromosomes. (wikipedia.org)
There's all sorts of mechanisms and structures in place that would allow for the division and faithful reproduction of those chromosomes. (gizmodo.com)

The study sheds light on how organisms have evolved to address such imbalances through a process called sex chromosome dosage compensation, or SCDC. (newswise.com)
Sex chromosome dosage compensation comes into play for individuals who have mismatched sex chromosomes. (newswise.com)
The study represents not only the first such study to analyze sex chromosome dosage compensation in turtles, but the findings also show that remarkably, temperature appears to affect the SCDC process in the turtles. (newswise.com)

The Weill Cornell Medicine investigators demonstrated that XIST is not alone empowered to turn off an X chromosome in every cell of a female mammal. (drugdiscoverynews.com)

The phenomenon of the process of linkage further demonstrates that why in fruit fly red-eye and grey-body colour occur in the same individuals. (gkscientist.com)
The Human-Specific BOLA2 Duplication Modifies Iron Homeostasis and Anemia Predisposition in Chromosome 16p11.2 Autism Individuals. (harvard.edu)
It results from a chromosomal abnormality where cells of affected individuals contain a third copy of chromosome 21 (1% of the human genome). (unige.ch)

DNA topology is dependent on axis proteins during eukaryotic cellular processes. (bham.ac.uk)

Man has 46 chromosomes and its linkage group is 23. (gkscientist.com)

Orthologous to human SMC5 (structural maintenance of chromosomes 5). (nih.gov)
Whereas canonical chromothripsis profiles display oscillations between two copy-number states, a considerable fraction of events involve multiple chromosomes and additional structural alterations. (lu.se)

Our work involving studies of tetraploid, triploid and diploid mouse ES cells revealed that initiation of XCI is a stochastic process, and indicated the presence of X-linked activators of XCI. (erasmusmc.nl)

This process would shrink the pseudoautosomal region in favour of expanding X- and Y-specific regions, creating a male supergene on the Y chromosome containing multiple colouration loci and thereby resolving sexually antagonistic selection. (nature.com)

The addition of methyl groups enables XIST to function to inactivate the X chromosome. (drugdiscoverynews.com)
When they removed DC1 from the cells, XIST was unable to turn off the X chromosome. (drugdiscoverynews.com)
Methylation of XIST is the switch that starts the process, recruiting DC1, and subsequently the proteins that inactivate the X chromosome. (drugdiscoverynews.com)
Yildirim says a long, noncoding RNA molecule called Xist (X-inactive specific transcript -- pronounced "exist") is the key to this process. (duke.edu)
It's well-known that Xist is crucial to initiate silencing on one X chromosome, but her lab is trying to figure out how Xist maintains the silence of the inactive X chromosome and how this process is essential during mammalian development. (duke.edu)
Yildirim thinks there's an important link between Xist and cancer because some cancer cells are seen to lack the inactivated clump of X chromosome that Xist creates, which is known as the Barr body in human cells. (duke.edu)
The question was, is Xist loss or change in the amount of active X-chromosome a cause or a consequence of cancer? (duke.edu)

If we can understand how the normal X chromosome is turned off, we can start to figure out how to turn it back on and get the body to produce those necessary proteins," Jaffrey said. (drugdiscoverynews.com)
In all eukaryotes, chromosome segregation is carried out by the spindle, which consists of microtubules and associated proteins. (harvard.edu)
Each chromosome consists of one very long molecule of DNA twisted around proteins. (carnivorousplants.org)

Anatomy65

Organisms14

Diseases33

Chemicals and Drugs31

Analytical, Diagnostic and Therapeutic Techniques and Equipment23

Psychiatry and Psychology2

Phenomena and Processes162

Disciplines and Occupations2

Anthropology, Education, Sociology and Social Phenomena1

Information Science4

Health Care1

Genes44

Extra chromosome8

Aberrations1

Randomly inactivated in every cell1

Gene19

Numbers of sex chromosomes2

Autosomes6

Independently evolved sex1

Arrangement of chromosomes2

Homologous chromosomes2

Five chromosomes2

Specific chromosomes2

Abnormalities3

Meiosis3

Mammals4

Species17

Meiotic cell cycle1

Drosophila3

Inactivation5

Condensation1

Small chromosome1

Paternal5

Researchers4

Organism2

Trisomy 211

Telomeres4

Evolutionary2

Heteromorphic2

Males2

Genetics2

Replication4

Genomic3

Abstract1

Abnormal2

Interstitial1

Chromosomal segment1

Molecular6

Karyotype1

Pair7

Recombination suppression1

Diseases4

Autosomal2

Genome evolution2

Protein4

Scientists4

Genetic material2

Populations3

Suppression1

Syndrome2

Structures2

Dosage compensation3

Female mammal1

Individuals3

Eukaryotic1

Linkage group1

Structural2

Stochastic1

Antagonistic1

XIST7

Proteins3