Chromosome fragile sites. Medical search. Frequent questions

These sites are associated with an increase in CHROMOSOME FRAGILITY . (nih.gov)
The overall goal of my research is to understand mechanisms of genome stability that operate at repetitive DNA, and how they collaborate to protect against repeat expansions and chromosome fragility. (tufts.edu)
The causes of chromosome fragility are not well understood, but the results can be significant: a broken chromosome is vulnerable to loss or rearrangement, which can lead to cancer or other genetic diseases. (tufts.edu)
My lab is interested in the basis for chromosome fragility at common fragile sites, which are often found deleted or rearranged in cancer cells. (tufts.edu)
We discovered that a sequence within the human site FRA16D containing a polymorphic AT repeat can cause fragility on a yeast chromosome, and can stall replication forks. (tufts.edu)
Whilst the majority of fragile X individuals have been found to have a characteristic mutation in the FMR1 gene, a small proportion of individuals exhibiting fragility have no such mutation. (ox.ac.uk)
Investigation of the site of chromosome fragility in these FMR1 mutation negative, fragile X site positive individuals, has identified a second site of fragility, FRAXE. (ox.ac.uk)
Here we describe a fragile X site positive, FMR1 mutation negative family, in which chromosome fragility is not due to the FRAXA or FRAXE but is due to a third site designated FRAXF. (ox.ac.uk)
The identification of a third fragile site in this small region of the X chromosome provides an opportunity to extend our studies of the molecular nature of chromosome fragility. (ox.ac.uk)
So called because the X chromosome possesses a site of fragility. (metaglossary.com)

Fragile X is the most common cause of mental retardation after Down syndrome . (medscape.com)
Rare fragile sites can lead to genetic disease such as fragile X mental retardation syndrome, myotonic dystrophy, Friedrich's ataxia, and Huntington's disease, most of which are caused by expansion of repeats at the DNA, RNA, or protein level. (wikipedia.org)
NEUROBIOLOGY AND GENETICS OF FRAGILE X SYNDROME Release Date: April 6, 2000 RFA: HD-00-015 National Institute of Child Health and Human Development ( http://www.nichd.nih.gov ) National Institute of Mental Health ( http://www.nimh.nih.gov ) Letter of Intent Receipt Date: June 1, 2000 Application Receipt Date: July 17, 2000 THIS RFA USES THE "MODULAR GRANT" AND "JUST-IN-TIME" CONCEPTS. (nih.gov)
PURPOSE The National Institute of Child Health and Human Development (NICHD), through its Mental Retardation and Developmental Disabilities (MRDD) Branch, and the National Institute of Mental Health (NIMH), in collaboration with the FRAXA Research Foundation, invite investigators to submit new, innovative research grant applications addressing the epidemiology, genetics, and neurobiology of Fragile X syndrome. (nih.gov)
Although considerable progress has been made recently in several areas of research on Fragile X syndrome, there was consensus among workshop participants that further progress in those and other areas is now needed. (nih.gov)
Fragile X syndrome, one of the most common causes of mental retardation and neuropsychiatric disease in humans, occurs as a result of the production of "fragile sites" by trinucleotide repeat expansion of at least one gene located on the X chromosome. (nih.gov)
The purpose of this RFA is to stimulate research designed to increase our knowledge base relevant to Fragile X syndrome in these and other research areas by encouraging applications that include, but are not limited to, developmental neurobiology, pathophysiology, genetics, proteomics, epidemiology, structure-function correlations, and clinical studies that have a direct link to Fragile X syndrome. (nih.gov)
This RFA, Neurobiology and Genetics of Fragile X Syndrome, is related to one or more of the priority areas. (nih.gov)
This predated by five years Sutherland's 3 description of the tissue culture medium required to diagnose fragile X syndrome (FRAXA) chromosomally, an event which highlighted the significance of X linked mental retardation (XLMR) and kindled the search for XLMR genes. (bmj.com)
Women who carry a variation of the gene for Fragile X syndrome are at higher risk for Fragile X-Associated POI (FXPOI) . (nih.gov)
7 Fragile X syndrome is the most common inherited form of intellectual and developmental disability, but women with FXPOI do not have Fragile X syndrome itself. (nih.gov)
Instead, they have a change or mutation in the same gene that causes Fragile X syndrome, and this change is linked to FXPOI. (nih.gov)
Turner syndrome is a condition in which a girl or woman is partially or completely missing an X chromosome. (nih.gov)
Women with Turner syndrome are X0, meaning one of the X chromosomes is missing. (nih.gov)
Fragile X syndrome (FXS), the most common inherited cause of intellectual disability (ID) worldwide, is caused by the expansion of a CGG repeat in the fragile X mental retardation gene ( FMR-1 ) gene. (samj.org.za)
To review, retrospectively, the genetic services for FXS and other FMR-1 -related disorders - including fragile X-associated tremor/ataxia syndrome (FXTAS) and FMR-1 -related primary ovarian insufficiency (POI) - at the Division of Human Genetics, Johannesburg, for diagnostic, carrier and prenatal genetic testing. (samj.org.za)
3 Fragile X syndrome (FXS) is the most common inherited cause of ID in all populations. (samj.org.za)
It is a rare, folic acid-sensitive fragile site associated with FRAGILE X SYNDROME . (nih.gov)
60], Fragile X syndrome is the most "translated" human neurodevelopmental disorder under study. (labourfilms.ca)
Fragile X syndrome ( FXS) is a genetic disorder characterized by mild-to-moderate intellectual disability. (labourfilms.ca)
11] However, due to genetic anticipation and X-inactivation in females, the inheritance of Fragile X syndrome does not follow the usual pattern of X-linked dominant inheritance, and some scholars have suggested discontinuing labeling X-linked disorders as dominant or recessive. (labourfilms.ca)
3.0.CO;2-O, "What can we learn about autism from studying fragile X syndrome? (labourfilms.ca)
The FXAA provides support to families affected by Fragile X syndrome. (labourfilms.ca)
Greg Peate (centre) with his sons Peter McKay and Geoffrey Smith, who both suffer from Fragile X syndrome. (labourfilms.ca)
Fragile X syndrome (FXS) is a genetic disorder. (labourfilms.ca)
NIH-supported scientists at Seaside Therapeutics in Cambridge, Mass., are beginning a clinical trial of a potential medication designed to correct a central neurochemical defect underlying Fragile X syndrome, the most common inherited cause of intellectual disability. (nih.gov)
The changes in turn appear to be the mechanism for learning deficits in Fragile X syndrome. (nih.gov)
Now, with the initiation of this first clinical study, we move one step closer to understanding how this novel candidate may play a critical role in improving the lives of individuals with Fragile X Syndrome. (nih.gov)
Fragile X syndrome is the most common inherited cause of intellectual disability, affecting an estimated 1 in 4,000 males and 1 in 6,000 females. (nih.gov)
People with Fragile X syndrome may have anxiety and attention deficit hyperactivity disorder. (nih.gov)
About one-third of males with Fragile X syndrome also have autism or autistic-like behavior that affects communication and social interaction. (nih.gov)
If results suggest that the medication is safe and tolerable, the study will progress to a phase 2 test of dosage and efficacy in adults with Fragile X syndrome. (nih.gov)
For more information on clinical trials related to Fragile X syndrome, visit the Clinical Trials website. (nih.gov)
2011. 62:411-29 First published online as a Review in Advance on FMRP, metabotropic glutamate receptor, autism, mental retardation, November 19, 2010 protein synthesis, long-term depression The Annual Review of Medicine is online atmed.annualreviews.org This article's doi: Fragile X syndrome (FXS) is the most common inherited form of men- tal retardation and a leading known cause of autism. (2medicalcare.com)
and ( c ) most disorders do not have a single FRAGILE X SYNDROME major genetic cause but are the result of a plethora of individ-ual mutations and gene copy number variations (2). (2medicalcare.com)
Single-gene Fragile X Syndrome disorders such as FXS are therefore particularly valuable as mod- FXS, originally known as Martin-Bell syn- els for more genetically complex disorders such as autism. (2medicalcare.com)
However, subsequent molecular studies did not confirm the presence of fragile-X syndrome. (elsevierpure.com)
This group of human diseases includes Fragile X Syndrome (FXS), Friedreich ataxia (FRDA), Huntington disease, and Myotonic Dystrophy. (nih.gov)
200 repeats have a learning disability and a variety of problems, including depression and anxiety, both men and women who inherit an FMR1 gene with 55-200 repeats are at risk of a neurodegenerative disease known as Fragile X-associated tremor and ataxia syndrome (FXTAS). (nih.gov)
The expression of FRAXA is associated with the fragile X syndrome, the most prevalent form of inherited mental retardation whilst the expression of FRAXE is associated with a rarer and comparatively milder form of mental handicap. (ox.ac.uk)
Folic acid deprivation in the culture medium induces folate-sensitive rare fragile sites, such as FRAXA which is responsible for the fragile X mental retardation syndrome. (genome-integrity.org)
Samples from five Fragile X syndrome patients, diagnosed using cytogenetic and molecular methods, as well as from their parents and five controls were included in the study. (genome-integrity.org)
The most common genetic cause of mental retardation after Down's syndrome, the fragile X syndrome, is associated with the occurrence of a fragile site at Xq27.3. (elsevierpure.com)
FRAXA is unique amongst fragile sites in that it is intimately involved with a specific clinical phenotype, the fragile X syndrome. (ox.ac.uk)
In striking contrast to the situation in fragile X syndrome, affected males may have affected daughters. (ox.ac.uk)
Fragile X syndrome (FXS) is a genetic condition, marked by inherited intellectual disability, especially in boys. (papermasters.com)
About half of all children diagnosed with fragile X syndrome also meet criteria for autism spectrum disorder . (papermasters.com)
Anyone diagnosed with fragile X syndrome will present on the continuum of learning disabilities , from displaying normal intelligence to severe intellectual disability. (papermasters.com)
Additionally, between 15 and 60% of cases are co-current with autism spectrum disorder, and it is suspected that fragile X syndrome is the genetic cause of autism in such cases. (papermasters.com)
Fragile X syndrome results from a mutation in the FMR1 gene, which is on the X chromosome. (papermasters.com)
There are currently no treatments or cures for fragile X syndrome. (papermasters.com)
Additionally, individuals with FXS are at a greater risk of developing seizures, estimated around 14% of all boys and 6% of girls with fragile X syndrome. (papermasters.com)
Klinefelter Syndrome - Research papers on Klinefelter Syndrome examine the chromosomal disorder that occurs randomly and is identified via a karyotype with the presence at least one extra X chromosome. (papermasters.com)
Prader Willi Syndrome - Research papers on Prader Willi Syndrome discuss the genetic disorder that is primarily caused when the paternal chromosome 15 is deleted. (papermasters.com)
Fragile X Syndrome research papers discuss the genetic condition that is marked by an inherited intellectual disability. (papermasters.com)
The syndrome is also known as FRAXA (the fragile X chromosome itself) and as the Martin-Bell syndrome. (metaglossary.com)
However, the preferred name is fragile X syndrome. (metaglossary.com)
Fragile X syndrome (FXS) is caused by the maternal expansion of an unstable CGG-repeat tract located in the first exon of the FMR1 gene. (frontiersin.org)
Screening of potential participants has begun in a Phase 2a trial that will test Nova Mentis Life Science's NM-1001, a microdose of the psychedelic molecule psilocybin, in adults with fragile X syndrome. (fragilexnewstoday.com)
PureTech Health is planning a Phase 2 clinical trial to test its lead therapeutic candidate LYT-300 - an oral formulation of allopregnanolone - in people with fragile X-associated tremor/ataxia syndrome (FXTAS). (fragilexnewstoday.com)
Fragile X syndrome is a genetic condition associated with cognitive impairment, learning and behavioral challenges, and several physical features. (fragilexnewstoday.com)

Copy number variants (CNVs) resulting from genomic deletions and duplications and common fragile sites (CFSs) seen as breaks on metaphase chromosomes are distinct forms of structural chromosome instability precipitated by replication inhibition. (nih.gov)
3. Increased genetic instability of the common fragile site at 3p14 after integration of exogenous DNA. (nih.gov)
6. Stably transfected common fragile site sequences exhibit instability at ectopic sites. (nih.gov)
10. Chromosomal fragile site FRA16D and DNA instability in cancer. (nih.gov)
Chromosome instability is a critical event in cancer progression. (nih.gov)
Chromosome instability at fragile sites can be evaluated by biomarkers of genomic instability such as frequency of micronuclei (MN). (genome-integrity.org)
Hosseini SA, Horton S, Saldivar JC , Miuma S, Stampfer M, Heerema N, Huebner K. Common chromosome fragile sites in human and murine epithelial cells and FHIT/FRA3B loss-induced global genome instability. (saldivarlab.org)

Further correlation of the degree of expansion and expression of clinical manifestations of the Fragile X phenotype, particularly behavioral manifestations such as autism, autism spectrum disorders, attention deficit hyperactivity disorder (ADHD), and anxiety disorders, is needed. (nih.gov)
Few studies have examined the occurrence of chromosome abnormalities in a large sample of patients with autism and related pervasive developmental disorders (PDDs). (elsevierpure.com)
These results suggest that chromosome abnormalities are uncommon in traditional autism and may be relatively more common in people with PDDNOS. (elsevierpure.com)
Weidmer-Mikhail, E , Sheldon, S & Ghaziuddin, M 1998, ' Chromosomes in autism and related pervasive developmental disorders: A cytogenetic study ', Journal of Intellectual Disability Research , vol. 42, no. 1, pp. 8-12. (elsevierpure.com)

Chromosomal fragile sites (CFSs) are genomic regions prone to form gaps or breaks on metaphase chromosomes. (uniklinikum-jena.de)

Fragile sites at 16q22 are not at the breakpoint of the chromosomal rearrangement in AMMoL. (nih.gov)
The sites most sensitive to aphidicolin damage include the 'hot spots' seen under conditions of thymidylate stress and in studies of spontaneous chromosomal damage. (neb.com)
2. Preferential integration of marker DNA into the chromosomal fragile site at 3p14: an approach to cloning fragile sites. (nih.gov)
Thema: "Chromosomal fragile sites as markers of cancerogenic rearrangements - aspects of nuclear architecture and molecular localization. (uniklinikum-jena.de)
Changes in the number of chromosomes and variations in the copy number of chromosomal regions are described in various pathological conditions, such as cancer and aneuploidy, but also in normal physiological condition. (benthamscience.com)
Our initial view of DNA replication and mitotic preservation of chromosomal integrity is now challenged as new technologies allow the observation of mosaic somatic changes in copy numbers of chromosome regions of different sizes. (benthamscience.com)
Cancer-associated chromosomal changes often involve regions containing fragile sites. (nih.gov)

This region is known as a fragile area because it is unstable and prone to breakage and rearrangement. (medlineplus.gov)
In addition to triplet repeats, several other types of microsatellite sequences act as "common" fragile sites on human chromosomes - sites present in all individuals that are prone to breakage. (tufts.edu)
To identify pancreatic cancer biomarkers, we focused on a genomic interval proximal to the most common fragile site in the human genome, chromosome 3p12, which undergoes smoking-related breakage, loss of heterozygosity, and homozygous deletion as an early event in many epithelial tumors, including pancreatic cancers. (nih.gov)
Finally, MN-FISH analysis allowed confirming that the increase in MN frequency is due to a higher sensitivity to chromosome breakage along the X chromosome. (genome-integrity.org)
Malformation (or even breakage) of the X chromosome associated with moderate mental retardation. (metaglossary.com)

5. Direct cloning of DNA sequences from the common fragile site region at chromosome band 3p14.2. (nih.gov)
9. Identification of unstable sequences within the common fragile site at 3p14.2: implications for the mechanism of deletions within fragile histidine triad gene/common fragile site at 3p14.2 in tumors. (nih.gov)
15. Cloning of genetically tagged chromosome break sequences reveals new fragile sites at 6p21 and 13q22. (nih.gov)
The miRNAs that use this mechanism find their complementarity sites in the coding sequences of the mRNAs. (getstayhealthy.com)
View and Analyze sequences in NCBI Virus · ICTV homepage Information from sequence entries. (firebaseapp.com)
2021-4-12 · High-quality chromosome-scale haplotype sequences of diploid genomes, polyploid genomes, and metagenomes provide important insights into genetic variation associated with disease and biodiversity. (firebaseapp.com)

It is the commonest inherited cause of mental retardation, and results from a dynamic mutation in a gene on the long arm of the X chromosome. (medscape.com)
200 CGG repeats and are classified as having a full mutation (FM) which is associated with hypermethylation of an upstream gene promoter region (CpG island) and silencing of FMR-1 gene transcription which results in the absence of the gene product, fragile X mental retardation protein (FMRP). (samj.org.za)
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)
Boys who inherit a Fragile X gene mutation usually develop the disorder, while girls who inherit the mutation are more likely to be carriers. (metaglossary.com)
A mutation causes a repetition of the letters CGG in a gene on the X chromosome. (metaglossary.com)

Understanding the genetic basis of psychiatric and neurological In this review, we describe recent progress in disorders eventually will lead to insights into how the brain func- the study of one of these disorders, fragile X tions differently in these diseases. (2medicalcare.com)
Both lines of evidence suggest genetic variants associated with gene expression variation are located predominantly near transcription start sites. (biomedcentral.com)
However, studying the specific role of BECN1 at the genetic level is complicated due to its genomic proximity to BRCA1 on both human (chromosome 17) and murine (chromosome 11) genomes. (prolekarniky.cz)

Fine mapping of gene probes and anonymous DNA fragments to the long arm of chromosome 16. (nih.gov)

Despite FXS being the most common heritable cause of intellectual disability, we still don't fully understand how the repeats, which are located in the FMR1 gene on the X chromosome, are responsible for disease symptoms," Usdin says. (nih.gov)
a common type of inherited mental disability, caused by a defective gene on the X chromosome. (metaglossary.com)
In Fragile X, the repeating triplet is CGG, cytosine-guanine-guanine, in a gene on the X chromosome. (metaglossary.com)

Three fragile sites, FRAXA, FRAXE and FRAXF lie in the Xq27-28 region of the human X chromosome. (ox.ac.uk)
The cytogenetic expression of the folate sensitive fragile site, FRAXE, is due to the expansion of a GCC repeat in proximal Xq28 of the human X chromosome and is associated with a mild form of mental handicap. (ox.ac.uk)

To our knowledge, this is the first documented case suggesting a link between FRA16B/C and chromosome 16 abnormalities in embryos and sperm from a carrier. (nih.gov)
They found that tumors with detectable EBV also had an unusually high number of chromosome 11 abnormalities. (nih.gov)

The cloning of FRAXF: trinucleotide repeat expansion and methylation at a third fragile site in distal Xqter. (ox.ac.uk)
The identification of a third fragile site, FRAXF, in Xq27--q28 distal to both FRAXA and FRAXE. (ox.ac.uk)
Using fluorescent in situ hybridisation (FISH) this site is shown to lie over 1Mb distal to FRAXA. (ox.ac.uk)
The probe StB12.3 has been used to screen the FMR-1 gene in 42 pedigrees with a distal Xq fragile site for expansion of the CCG repeat and aberrant methylation of the FRAXA locus. (ox.ac.uk)

The work is the outcome of basic research that traced how an error in the fragile X mental retardation gene (FMR1) leads to changes in brain connections, called synapses. (nih.gov)
People with Fragile X have DNA mutations in the FMR1 gene that, in effect, turn off the gene. (nih.gov)
On average, boys with a complete fragile X mental retardation 1 (FMR1) will have an IQ around 40. (papermasters.com)
Fragile X is caused by mutations in the fragile X mental retardation 1 ( FMR1 ) gene, located in the X chromosome. (fragilexnewstoday.com)

We describe here the cloning of the third fragile site, FRAXF, and demonstrate that it involves the expansion of a (GCCGTC)n(GCC)n compound array. (ox.ac.uk)

The woman was a carrier of a balanced reciprocal translocation, t(11;22)(q23;q11.2), and the man presented high expression of the fragile site 16q22.1 (FRA16B/C) in peripheral blood lymphocytes. (nih.gov)
loss of expression of the fragile X mental retardation protein (FMRP), All rights reserved an RNA-binding protein that negatively regulates protein synthesis. (2medicalcare.com)
However, there is no simple relationship between the degree of methylation and either the level of expression of the fragile site or the severity of the clinical phenotype. (elsevierpure.com)

Randomised clinical trials comparing women being tested regardless of family history (intervention group) with women tested only when there is a family history of either fragile X and/or other undiagnosed mental illness/impairment (control group). (medscape.com)
With the rapid development of next-generation sequencing technology, chromosome structural variation has gradually gained increased clinical significance in tumorigenesis. (biomedcentral.com)

This initiative was developed primarily in response to the 1998 NICHD- sponsored "Workshop on Fragile X: Future Research Directions. (nih.gov)

Both the FRAXA and FRAXE sites have been cloned and the fragile site expression found to be due to the expansion of analogous CGG/GCC trinucleotide repeat arrays. (ox.ac.uk)

This region includes more than 300 copies of an 18-letter sequence that looks quite similar to the EBNA1-binding sites in its own viral genome. (nih.gov)
After the completion of a draft human genome sequence, the International Human Genome Sequencing Consortium has proceeded to finish and annotate each of the 24 chromosomes comprising the human genome. (inra.fr)
Chromosome 3 comprises just four contigs, one of which currently represents the longest unbroken stretch of finished DNA sequence known so far. (inra.fr)

Total and site-specific damage was dose dependent and greatly increased when folic acid was removed from the medium. (neb.com)

Almost all cases of FXS are caused by the expansion of a CGG repeat in the 5' untranslated region of the fragile X mental retardation gene ( FMR-1 ) (OMIM #309550) at the FRAXA fragile site Xq27.3. (samj.org.za)
During an ongoing study on X-linked mental retardation, we ascertained a large family in which mild mental retardation was cosegregating with a fragile site at Xq27-28. (ox.ac.uk)
A candidate gene for mild mental handicap at the FRAXE fragile site. (ox.ac.uk)
A hereditary mental disorder, partially explained by genomic imprinting and the addition of nucleotides to a triplet repeat near the end of an X chromosome. (metaglossary.com)
If you have a family history of mental retardation, testing can determine whether Fragile X is responsible and whether you are a carrier. (metaglossary.com)

These sites are called fragile sites, and can occur commonly as naturally present in most mammalian genomes or occur rarely as a result of mutations, such as DNA-repeat expansion. (wikipedia.org)

18. Regional chromosome localization of human papillomavirus integration sites near fragile sites, oncogenes, and cancer chromosome breakpoints. (nih.gov)

is a spectrum of symptoms that correlate with autistic disorder, in this case resulting from a defect on the X chromosome. (metaglossary.com)

With FISH the fragile site was located within the FRAXE region. (ox.ac.uk)

4. Common fragile site FRA11G and rare fragile site FRA11B at 11q23.3 encompass distinct genomic regions. (nih.gov)

Usually, males, who have only a single X chromosome, are more severely affected than females. (nih.gov)
The array is also expanded in cytogenetically positive carrier females from the family originally used to define the FRAXF site. (ox.ac.uk)
Cytogenetically the fragile site was always present in affected males and was not always present in affected females. (ox.ac.uk)
While some females with fragile X have significant intellectual impairment, the majority has either normal IQ or learning disabilities. (metaglossary.com)

7. Common fragile sites and cancer: targeted cloning by insertional mutagenesis. (nih.gov)

Reference: DNA polymerase alpha inhibition by aphidicolin induces gaps and breaks at common fragile sites in human chromosomes. (neb.com)
The hot spots induced by aphidicolin represent a new class of fragile sites which we term common fragile sites. (neb.com)
Large transcription units unify copy number variants and common fragile sites arising under replication stress. (nih.gov)
8. Common fragile sites are preferential targets for HPV16 integrations in cervical tumors. (nih.gov)
12. Human papillomavirus type 16 integrations in cervical tumors frequently occur in common fragile sites. (nih.gov)
14. Common fragile sites as targets for chromosome rearrangements. (nih.gov)
16. Induction of antiestrogen resistance in human breast cancer cells by random insertional mutagenesis using defective retroviruses: identification of bcar-1, a common integration site. (nih.gov)
19. Characterization of the human common fragile site FRA2G. (nih.gov)
20. Common fragile sites (CFS) and extremely large CFS genes are targets for human papillomavirus integrations and chromosome rearrangements in oropharyngeal squamous cell carcinoma. (nih.gov)
We studied the involvement of miRNAs located on chromosomes 11q and 22q that participate in the most common translocation in ES. (oncotarget.com)
It also includes a chemokine receptor gene cluster as well as numerous loci involved in multiple human cancers such as the gene encoding FHIT, which contains the most common constitutive fragile site in the genome, FRA3B. (inra.fr)

Where the protein accumulates, the chromosome becomes more prone to breaking for reasons that aren't yet fully known. (nih.gov)
And these so-called fragile sites are inherently prone to breaking. (nih.gov)

Cytogenetic manifestations of amplified DNA include self-replicating extrachromosomal elements called d ouble m inutes (DMs), amplified regions on a single chromosome ( h omogeneously s taining r egions, HSRs) or amplified regions distributed throughout the genome [ 5 ]. (biomedcentral.com)

Since I have daughters, I also worry if theyll have the ovarian insufficiency that can come with fragile X, and if theyll be able to have children of their own. (labourfilms.ca)
Women are also at risk of a form of infertility known as Fragile X-associated primary ovarian insufficiency (FXPOI). (nih.gov)

Karen Usdin investigates how multiple copies of a short DNA repeat give rise to the Fragile X-related disorders. (nih.gov)

Gene conversion is now thought to be a type of non-Mendelian segregation of heterozygous markers near the recombination initiation site. (preprints.org)
Using microdisected markers close to the fragile site, we have been able to test these hypotheses. (elsevierpure.com)

It was aimed to analyse the chromosome content of MN in Fragile X cells during folate deprivation by the MN-fluorescence in situ hybridization (FISH) method. (genome-integrity.org)

The more repeats of this code on a person's X chromosome, the more impaired he or she is likely to be. (metaglossary.com)

This gene is located near a folate-sensitive fragile site, and CGG-repeat expansion in the promoter of this gene which affects transcription has been detected in individuals containing this fragile site on chromosome 12. (utsouthwestern.edu)

In the cancer background, excess CENP-A is deposited ectopically on chromosome arms, including 8q24/ cMYC locus, by invading transcription-coupled H3.3 chaperone pathways. (nih.gov)

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)

Imprinting effect in premature ovarian failure confined to paternally inherited fragile X premutations. (ru.nl)

The fragile X site, which can also be induced by thymidylate stress, was not induced by aphidicolin in lymphocytes, suggesting a separate mechanism for its induction. (neb.com)
Aphidicolin represents a novel tool for detection of hot spots on human chromosomes through the mechanism of DNA polymerase alpha inhibition. (neb.com)
The current review suggests that transpositional recombination and site-specific recombination should be initiated by copy choice during DNA synthesis rather than break/join mechanism. (preprints.org)
The complementarity sites for the miRNAs that use this mechanism are located in the non-translated regions, towards the 3′ end of the mRNA (3'UTR areas). (getstayhealthy.com)

LINX, an interpretation tool, leverages the integrated structural variant and copy number calling to cluster individual structural variants into higher order events and chains them together to predict local derivative chromosome structure. (biorxiv.org)

Furthermore, a transgene cassette carrying specific 8q24-derived lncRNA integrated into a naïve chromosome locus recruits CENP-A to the new location in a cis-acting manner. (nih.gov)
These data provide a plausible mechanistic link between locus-specific oncogenic lncRNAs, aberrant local chromatin structure, and the generation of new epigenetic memory at a fragile site in human cancer cells. (nih.gov)
Chromosome 8q24/ cMYC locus is a stable CENP-A ectopic site for CENP-A. (nih.gov)

They are frequently situated in fragile sites and regions of amplification or loss of heterozygosity associated with cancer. (getstayhealthy.com)

Site-specific recombination results from another distinct model. (preprints.org)

1. Preferential integration of a transfected marker gene into spontaneously expressed fragile sites of a breast cancer cell line. (nih.gov)
A ) Graphical illustration of CENP-A peaks on chromosome 8 from normal colon cells (huEpiCol) and SW480 colon cancer cells. (nih.gov)

Usually, all cells in an individual in a given species (plant or animal) show a constant number of chromosomes, which constitute what is known as the karyotype defining this species (see also List of number of chromosomes of various organisms), although some species present a very high karyotypic variability. (wikipedia.org)
In EBV-infected cells, increasing the amount of EBNA1 protein led to more chromosome 11 breaks. (nih.gov)
The findings suggest that people will vary in their susceptibility to EBNA1-induced DNA breaks along chromosome 11 based on the amount of EBNA1 protein in their latently infected cells. (nih.gov)
Another patient showed an abnormal fragile site at Xq27 in three out of 100 cells. (elsevierpure.com)
An accumulation of MN in Fragile X patients, mainly containing T (+) or C (+) MN or T (+) plus C (+) MN in binucleated cells was found. (genome-integrity.org)

We conclude that the expanded array corresponds to the FRAXF fragile site. (ox.ac.uk)

Chromosome fragile sites tend to form gap or break in chromosomes following when the cell exposed to replication stress. (genome-integrity.org)

Cattle-specific evolutionary breakpoint regions in chromosomes have a higher density of segmental duplications, enrichment of repetitive elements, and species-specific variations in genes associated with lactation and immune responsiveness. (inra.fr)

Theories to explain this unusual phenomenon include genomic rearrangements and methylation changes associated with a local block of reactivation of the X chromosome. (elsevierpure.com)

Anatomy9

Diseases9

Chemicals and Drugs2

Analytical, Diagnostic and Therapeutic Techniques and Equipment2

Phenomena and Processes17

Information Science1

FRAGILITY10

Syndrome61

Instability7

Autism4

Breaks on metaphase chromosomes1

Chromosomal7

Breakage5

Sequences6

Mutation5

Genetic3

Long arm of chromosome1

Gene on the X chromosome3

Human X chromosome2

Abnormalities2

Distal4

FMR14

Third fragile site1

Expression of the fragile3

Clinical2

19981

Trinucleotide1

Sequence3

Folic1

Mental5

Genomes1

Breakpoints1

AUTISTIC DISORDER1

FRAXE1

Genomic regions1

Females4

Cloning1

Common11

Prone2

Cytogenetic1

Ovarian insufficiency2

Disorders1

Markers2

Situ Hybridization1

Repeats1

Folate1

Transcription1

Occurrence1

Premutations1

Mechanism4

Structural1

Locus3

Loss of heterozygos1

Distinct1

Cancer2

Cells5

FRAXF1

Replication1

Duplications1

Rearrangements1