Homologous chromosomes are chromosome pairs of the same length, centromere position, and staining pattern, with genes for the same characteristics at corresponding Locus genetics loci . One Homology biology homologouschromosome is inherited from the organism s mother the other from the organism s father. ref name Campbell cite book author Reece, Jane Campbell, Neil title Biology publisher Benjamin Cummings location San Francisco year 2002 isbn 0 8053 6624 5 ref They pair synapsis synapse during meiosis , or cell division that occurs as part of the creation of gametes. Each chromosome pair contains genes for the same biological features, such as eye color, at the same locations locus genetics loci on the chromosome. Each pair, however, can contain the same allele both alleles for blue eyes or different alleles one allele for blue eyes and one allele for brown eyes for each feature. Non homologous ... of a pair of homologous chromosomes is biological inheritance inherited from a different parent . But polyploid organisms have more than two homologous chromosomes. Homologous chromosomes are similar in length, except for sex chromosome s in several taxa , where the X chromosome is considerably larger than the Y chromosome . These chromosomes share only small regions of homology biology homology . Humans have 22 pairs of homologous non sex chromosomes called autosomes , and one pair of sex chromosome ... from one of the two parents. In addition to the 22 pairs of homologous autosomes, female humans have a homologous pair of sex chromosomes X chromosome 2 Xs , while males have an X chromosome X and a Y chromosome . Homologous chromosomes are two pairs of sister chromatid s that have gone through the process of crossing over and meiosis. In this process the homologous chromosomes cross over ... to have genetic information from both parents, a mechanism for genetic variation. The homologous ... resources, and Comparative Chromosome Maps of the Human, Mouse, and Rat. http www.ncbi.nlm.nih.gov ... more details
animal and plant species are polyploid Xn They have more than two sets of homologouschromosome s. Plants ...For a non technical introduction to the topic Introduction to genetics A chromosome is an organized structure ... chromosome. 1 Chromatid one of the two identical parts of the chromosome after S phase ... E, Sourdille P, Salse J, et al. title A Physical Map of the 1 Gigabase Bread Wheat Chromosome 3B journal ..., although there are many exceptions to this rule. Also, cells may contain more than one type of chromosome ... evade apoptosis leading to the progression of cancer . In practice chromosome is a rather loosely ... is present. However, a large body of work uses the term chromosome regardless of chromatin content ... that often lack structural proteins. The word chromosome comes from the Greek language Greek ... original. Citation needed date April 2009 Wilhelm Roux suggested that each chromosome carries a different ... around 1902 by naming the chromosome theory of inheritance the Boveri Sutton Chromosome Theory Sutton ... Morgan , all of a rather dogmatic turn of mind. Eventually, complete proof came from chromosome .... ref In eukaryotes See also Eukaryotic chromosome fine structure Eukaryotes cell biology cells with nuclei ... in the cell s nucleus. Each chromosome has one centromere , with one or two arms projecting ... on gene prediction s. Total chromosome length is an estimate as well, based on the estimated size ... style text align right Chromosome Genes Total Nucleobase bases Sequenced bases ref Sequenced percentages ... Project. ref Chromosome 1 human 1 4,220 247,199,719 224,999,719 Chromosome 2 human 2 1,491 242,751,149 237,712,649 Chromosome 3 human 3 1,550 199,446,827 194,704,827 Chromosome 4 human 4 446 191,263,063 187,297,063 Chromosome 5 human 5 609 180,837,866 177,702,766 Chromosome 6 human 6 2,281 170,896,993 167,273,993 Chromosome 7 human 7 2,135 158,821,424 154,952,424 Chromosome 8 human 8 1,106 146,274,826 142,612,826 Chromosome 9 human 9 1,920 140,442,298 120,312,298 Chromosome 10 human 10 1,793 ... more details
Image HR in meiosis.svg thumb 275px alt Depiction of chromosome 1 after undergoing homologous recombination in meiosis Figure 1. During meiosis , homologous recombination can produce new combinations of genes as shown here between homologouschromosome similar but not identical copies of human chromosome 1 human chromosome 1 . Homologous recombination is a type of genetic recombination in which nucleotide ... title Repairing a double strand chromosome break by homologous recombination revisiting Robin Holliday ... 0 8153 4105 5 page 303 ref Compared to homologous chromosomes, which are similar to another chromosome ... because they are an identical copy of a given chromosome. In contrast to homologous recombination ... 3 overhang strand and the homologouschromosome. After strand invasion, a DNA polymerase ... invasion also forms a Holliday junction with the homologouschromosome. The double Holliday junctions ... on a homologouschromosome. Upon finding such a sequence, the single stranded nucleoprotein filament ... copy of chromosome 21 , is one of many abnormalities that result from such a failure of homologous ... as double strand breaks. Homologous recombination also produces new combinations of DNA sequences ... 48122761 57023651 69932405 ref Homologous recombination is also used in horizontal gene transfer ... homologous recombination varies widely among different organisms and cell types, most forms of it involve ... DNA molecules. Depending on how the two junctions are cut by enzyme s, the type of homologous recombination that occurs in meiosis results in either chromosomal crossover or non crossover. Homologous ... restoring the damaged DNA molecule as it existed before the double strand break. Homologous recombination ... for homologous recombination in protist s a diverse group of eukaryotic microorganisms has been interpreted ... that facilitate homologous recombination are topics of active research. Homologous recombination .... The development of gene targeting techniques that rely on homologous recombination was the subject ... more details
Context date October 2009 Desensitization of Receptor biochemistry receptors is a process whereby after prolonged agonist exposure, the receptor is uncoupled from its signaling cascade, and thus the biological effect of receptor activation is attenuated. High ligand concentrations are required to produce homologous desensitization . Homologous desensitization should not be confused with heterologous desensitisation , which has some similarities, but is a different process. The process of homologous desensitization is as follows using the Beta 2 adrenergic receptor sub 2 sub receptor as an example Agonist binds and activates receptor which changes to an active conformational state. Beta adrenergic receptor kinase BARK , a cytoplasmic kinase is activated and phosphorylation phosphorylates the C terminus of the sub 2 sub receptor. Such phosphorylation increases the affinity of arrestin arrestin for the receptor, resulting in uncoupling of the Gs alpha subunit subunit of the G proteins heterotrimeric G protein from the receptor producing desensitization. References Category Membrane biology Category G protein coupled receptors Category Signal transduction biology stub molecular cell biology stub ... more details
In chemistry , a homologous series is a series of organic compound s with a similar General formula General forms for organic compounds general formula , possessing similar chemical properties due to the presence of the same functional group , and shows a gradation in physical properties as a result of increase in molecular size and mass see relative molecular mass . For example, ethane has a higher boiling point than methane since it has more Van der Waals forces intermolecular forces with neighbouring molecules. This is due to the increase in the number of atoms making up the molecule. Each organic compound in a homologous series vary by an extra CH sub 2 sub from the previous compound. Alkane s paraffin s , alkene s olefins , ethers , and alkyne s acetylene s form such series in which members differ in mass by 14 atomic mass units. For example, the alkane homologous series begins with methane CH sub 4 sub , ethane C sub 2 sub H sub 6 sub , propane C sub 3 sub H sub 8 sub , butane C sub 4 sub H sub 10 sub , and pentane C sub 5 sub H sub 12 sub , each member differing from the previous one by a CH sub 2 sub group or 14 atomic mass units . Similarly, there is the alcohol homologous series that starts with methanol CH sub 4 sub O , ethanol C sub 2 sub H sub 6 sub O , as primary alcohols, isopropanol C sub 3 sub H sub 8 sub O as a simple secondary alcohol, and a simple tertiary alcohol ... constant in a homologous series, specific members of the series may have different structures or entirely ... text align center tr td Homologous series td td General formula td td Example td td Functional ... which converts one member of a homologous series to the next member. Homologous oxides Commons category Homologous series Homologous series are not unique to organic chemistry . Titanium , vanadium , and molybdenum oxides all form homologous series. E.g. V sub n sub O sub 2n 1 sub for 2 n 10 Unreferenced date December 2009 DEFAULTSORT Homologous Series Category Organic chemistry ar ... more details
Unreferenced stub auto yes date December 2009 Homologous temperature expresses the temperature of a material as a fraction of its melting point temperature using the Kelvin scale . For example, the homologous temperature of lead at room temperature is approximately 0.50 T sub H sub T T sub mp sub 298K 601K 0.50 . Solder T sub mp sub 183 C 456K at 0.85T sub mp sub or 115 C 388K , would thus be expected to have comparable properties to copper T sub mp sub 1085 C 1358K at 0.85T sub mp sub or 881 C 1154K . In electronics applications, where circuits typically operate over a 55 C to 125 C range, eutectic tin lead Sn63 solder is working at 0.48T sub mp sub to 0.87T sub mp sub . The upper temperature is high relative to the melting point from this we can deduce that solder will have limited mechanical strength as a bulk material and significant Creep deformation creep under stress. This is borne out by its comparatively low values for tensile strength, shear strength and modulus of elasticity. Citation needed date April 2009 Copper, on the other hand, has a much higher melting point, so foils are working at only 0.16T sub mp sub to 0.29T sub mp sub , and their properties are little affected by temperature. DEFAULTSORT Homologous Temperature Category Units of temperature Physics stub Measurement stub ... more details
Chromosome segregation is a step in cell reproduction or division, where chromosomes pair off with their similar homologouschromosome. In mitosis , a complete copy of each one is made. In meiosis , one chromosome from each pair migrates to opposite ends of the cell and the genes are split to make a gamete. ref cite book last Deppe first Carol title Breed your own Vegetable Varieties publisher Little, Brown & Company date 1993 pages 96 97 isbn 0 316 18104 8 ref For more information see Cell Cycle the Cell Cycle . References div class references small style moz column count 2 column count 2 references div Category Chromosomes ... more details
unreferenced date September 2009 Image with unknown copyright status removed Image Centromere.png right Image Chromosome upright.png frame Diagram of a duplicated and condensed metaphase eukaryotic chromosome. 1 Chromatid one of the two identical parts of the chromosome after S phase . 2 Centromere the point where the two chromatids touch, and where the microtubules attach. 3 Short arm p . 4 Long arm q . Several chromosome regions have been defined by convenience in order to talk about gene locations. Most important is the distinction between chromosome region p and chromosome region q . These are virtual regions that exist in all chromosome s. During cell division , the molecules that compose chromosomes DNA and protein s suffer a condensation process called the chromatin condensation , and forms a compact and small complex. In diploid organisms, homologous Chromosomes homologous chromosomes get attached to each other by the centromere . The centromere divides each chromosome into two regions the smaller one, which is the p region, and the bigger one, the q region. Usually, as a convention, the p region is represented in the upper part of an image while the q region is in the bottom part. At either end of a chromosome is a telomere , a cap of DNA that protects the rest of the chromosome from damage. The areas of the p and q regions close to the telomeres are the subtelomere s, or subtelomeric regions. The areas closer to the centromere are the pericentronomic regions. Finally, the interstitial regions are the parts of the p and q regions that are close to neither the centromere nor the telomeres, but are roughly in the middle of p or q . Image subtelomere copy.jpg left DEFAULTSORT Chromosome Regions Category Chromosomes ... more details
A balancer chromosome is a genetic tool used to prevent crossing over genetic recombination between homologouschromosome s during meiosis . Balancers are most often used in Drosophila melanogaster fruit fly genetics to allow populations of flies carrying heterozygous mutations to be maintained without constantly screening for the mutations. Balancer chromosomes have three important properties they suppress recombination with their homologs, carry dominant markers and negatively affect reproductive ... that synapsis between homologous chromosomes is disrupted. If crossing over between a balancer chromosome ... researchers to easily recognize flies that carry the balancer chromosome. By suppressing reproductive fitness when carried homozygously a balancer chromosome ensures that the population it is carried in does not become fixed for the balancer chromosome. Naming convention Balancer chromosomes are named for the chromosome they serve to stabilize and for the phenotypic or genetic marker the balancer ... 13 ref The naming of balancer chromosomes has been standardized as follows the first letter of the chromosome s name represents the number of the chromosome it stabilizes. F stands for the first chromosome, S stands for second, and T stands for third. The small fourth chromosome does not undergo ... inverted . The M is followed by a number to distinguish balancers of the same chromosome. Additionally .... For example, the commonly used TM3, Sb balancer is a balancer chromosome that stabilizes the third chromosome and carries a mutant Sb Stubble gene as a marker. All flies containing the TM3, Sb ... through a microscope. The 3 is to distinguish this from other third chromosome balancers, such as TM1 ... chromosomes i.e. TM6,Tb TM3,Ser on a balancer chromosome and a homozygous lethal, heterozygous visible mutant on the other, wild type chromosome i.e. D TM3,Ser . Most balancer chromosomes also carry ... double balanced at both the 2nd and 3rd chromosome in Drosophila are widely available. References ... more details
Image Chromosome X.svg 125px thumb right Scheme of the X chromatid Image Sd4hi unten crop.jpg thumb Nucleus of a female amniotic fluid cell. Top Both X chromosome territories are detected by Fluorescence ... . The X chromosome is one of the two sex determination system sex determining chromosome s in many animal species, including mammals the other is the Y chromosome . It is a part of the XY sex determination system and X0 sex determination system . The X chromosome was named for its unique properties by early researchers, which resulted in the naming of its counterpart Y chromosome, for the next letter ... 2007 05 01 science 01angi.html title For Motherly X Chromosome, Gender Is Only the Beginning ... Function The sex chromosomes X X are one of the 23 homologous pairs of chromosomes in a female. The X chromosome spans more than 153 million base pairs the building material of DNA and represents about ... in each cell. Females have two X chromosomes, whereas males have one X and one Y chromosome ... X chromosome from their father. Since the father retains his X chromosome from his mother, a human female has one X chromosome from her paternal grandmother father s side , and one X chromosome from her mother. Identifying genes on each chromosome is an active area of genetic research. Because researchers use different approaches to predict the number of genes on each chromosome, the estimated number of genes varies. The X chromosome contains about 2000 ref name Macmillan Science Library cite web author Macmillan Science Library title Genetics on X Chromosome year 2001 ref genes compared to the Y chromosome containing 78 ref name Harris cite web author Richard Harris title Scientists Decipher Y Chromosome url http www.npr.org templates story story.php?storyId 1303260 year 2003 ref genes ... to mutation s in genes on the X chromosome are described as X linked . The X chromosome carries ... ensures that females, like males, have one functional copy of the X chromosome in each body cell ... more details
Supernumerary chromosome could refer to B chromosome in some animals and plants Small supernumerary marker chromosome sSMC in humans disambig ... more details
Artificial chromosome may refer to Yeast artificial chromosome Bacterial artificial chromosome Human artificial chromosome P1 derived artificial chromosome disambig Long comment to avoid being listed on short pages ... more details
of its genes on itself instead of having a second, homologous, chromosome. When errors occur ...Image Chromosome Y.svg 125px right thumb Human Y chromatid The Y chromosome is one of the two Sex determination system sex determining chromosome s in most mammal s, including human s. In mammals, it contains the gene SRY , which triggers testicle testis development if present. The human Y chromosome is composed of about 60 million base pairs . DNA in the Y chromosome is passed from father to son, and Y ... chromosomes in each cell. Males have one Y chromosome and one X chromosome , while females have two X chromosomes. In mammals, the Y chromosome contains a gene, SRY , which triggers embryonic development ... Z chromosome , ref name Warren cite journal author Warren WC, Hillier LDW, Graves JAM, et al. title ... phenomena see Androgen insensitivity syndrome and Intersex . Origins and evolution Before Y chromosome ... author Muller, HJ title A gene for the fourth chromosome of Drosophila journal Journal of Experimental ... cite journal author Lahn B, Page D title Four evolutionary strata on the human X chromosome journal ... SeX chromosome specialization and degeneration in mammals journal Cell volume 124 issue 5 pages 901 14 year 2006 pmid 16530039 doi 10.1016 j.cell.2006.02.024 ref The chromosome with this allele became the Y chromosome, while the other member of the pair became the X chromosome. Over time, genes which were beneficial for males and harmful to or had no effect on females either developed on the Y chromosome ... without necessary genes formerly found on the Y chromosome, and females with unnecessary or even harmful genes previously only found on the Y chromosome. As a result, genes beneficial to males ... to preserve this male specific region. ref name Graves J.A.M. 2006 901 14 Over time, the Y chromosome ... with the X chromosome. As a result of this process 95 of the human Y chromosome is unable to recombine. Shrinking The human Y chromosome has lost 1,393 of its 1,438 original genes over the course ... more details
A chromosomes in some circumstances. The B chromosomes suppress homologous pairing which reduces multiple pairing between homologous chromosomes in Allopolyploidy allopolyploids . Bivalent pairing is ensured by a gene on chromosome 5 of the B genome Phlocus. The B chromosomes also have the following ... are not to be confused with marker chromosome s or additional copies of normal chromosomes as they occur in Trisomy Trisomies . Supernumerary chromosomes in fungi Chromosome polymorphisms are very common among fungi . Different isolates of the same species often have a different chromosome number ... significance. For example, it has been discovered that the supernumerary chromosome of the pea pathogen ... LW title B chromosome evolution journal Philos. Trans. R. Soc. Lond., B, Biol. Sci. volume 355 issue ... title Rapid suppression of drive for a parasitic B chromosome journal Cytogenetic and Genome Research ... Bakkali M, Camacho JP title The B chromosome polymorphism of the grasshopper Eyprepocnemis plorans in North Africa. IV. Transmission of rare B chromosome variants journal Cytogenet. Genome Res. volume ... JP title The B chromosome polymorphism of the grasshopper Eyprepocnemis plorans in North Africa III ... for B chromosome integration into the standard genome journal Chromosome Res. volume 11 issue ... title The B chromosome polymorphism of the grasshopper Eyprepocnemis plorans in North Africa II. Parasitic ..., Cabrero J, Bakkali M, L pez Le n MD, Perfectti F title Neutralization of a parasitic B chromosome in the grasshopper Eyprepocnemis plorans journal Chromosome Research volume 9 pages 106 year 2001 cite journal author Cabrero J, Lopez Leon MD, Bakkali M, Camacho JP title Common origin of B chromosome ... J, Lopez Leon MD, Perfectti F, Camacho JP title The B chromosome polymorphism of the grasshopper ... author Bakkali M, Cabrero J, L pez Le n MD, Perfectti F, Camacho JPM title B chromosome polymorphism ... http www.studenec.ivb.cz Projects B chromosome index.php B chromosomes in wood mice, genus Apodemus ... more details
Multiple issues orphan March 2011 unreferenced October 2010 expert subject March 2011 The polycentric chromosome is when more than 2 chromosome are present eg par ascaris 2 chromosome Mucor hiemalis in plant s have 2 chromosome. Adder s tongue fern have 1262 chromosome. In auto cantha or radiolorian there are 1682 chromosome. genetics stub DEFAULTSORT Polycentric Chromosome Category Chromosomes ... more details
Mechanism of Rearrangement , Molecular Cytogenetics 2008, 1 16 ref . See also Chromosome abnormalities References Schmidt et al. 1981. Ring chromosome 14 a distinct clinical entity. Journal of Medical ... more details
Chromosome engineering is the controlled generation of chromosomal deletions, inversions, or translocations with defined endpoints. ref Reviews Glossary. nature.com. N.p., n.d. Web. 15 Oct. 2009. http www.nature.com nrg journal v6 n7 glossary nrg1638 glossary.html. ref By combining chromosomal translocation , chromosomal inversion ,and chromosomal deletion , chromosome engineering has been shown to identify the underlying genes that cause certain diseases in mice. In coming years, it is very likely that chromosomal engineering will be able to do the same identification for diseases in humans, as well as all other organisms. ref Ramirez Solis, R., P. Liu, and A. Bradley. Chromosome Engineering in Mice. Public Med. N.p., n.d. Web. 17 Oct. 2009. http www.ncbi.nlm.nih.gov pubmed 7501018 . ref The Three Types of Chromosome Engineering class wikitable chromosomal deletion chromosomal inversion chromosomal translocation Chromosomal deletion is a mutation a genetic aberration in which a part of a chromosome or a sequence of DNA is missing. Chromosomal inversion is a chromosome rearrangement in which a segment of a chromosome is reversed end to end. Chromosomal translocation is a chromosome abnormality caused by rearrangement of parts between nonhomologous chromosomes. Experiments of Chromosome Engineering In an experiment pertaining to chromosome engineering that was conducted in 2006, it was found that chromosome engineering can be effectively used as a method of identifying the causes of genetic disorders such as the continuous gene and aneuploidy syndromes. The experiment was conducted by infecting mice with the human disease, ES, to see the effectiveness of chromosomal engineering ... chromosomes, or chromosome engineering, is an excellent and efficient method of determining underlying genes in genetic orders and diseases. In the future, chromosome engineering will experiment .... See also Genetics Chromosome Chromosomal deletion Chromosomal inversion Chromosomal translocation ... more details
Orphan date February 2009 A derivative chromosome der is a structurally rearranged chromosome generated either by a rearrangement involving two or more chromosomes or by multiple aberrations within a single chromosome e.g. an inversion and a deletion of the same chromosome, or deletions in both arms of a single chromosome . http ghr.nlm.nih.gov ghr glossary derivativechromosome The term always refers to the chromosome that has an intact centromere. Derivative chromosomes are designated by the abbreviation der when used to describe a Karyotype . The derivative chromosome must be specified in parentheses followed by all aberrations involved in this derivative chromosome. The aberrations must be listed from pter to qter and not be separated by a comma. For example, 46,XY,der 4 t 4 8 p16 q22 t 4 9 q31 q31 would refer to a derivative chromosome 4 which is the result of a translocation between the short arm of chromosome 4 at band 16 and the long arm of chromosome 8 at band 22, and a translocation between the long arm of chromosome 4 at band 31 and the long arm of chromosome 9 at band 31. Derivative chromosomes and other abnormalities could be drawn online using CyDAS online tools Hiller B, Bradtke J, Balz H and Rieder H 2004 CyDAS Online Analysis Site , http www.cydas.org OnlineAnalysis References An International System for Human Cytogenetic Nomenclature, Shaffer, L.G., Tommerup N. eds S. Karger, Basel 2005 Category Chromosomes genetics stub ... more details
Image Single Chromosome Mutations.png thumb right The three major single chromosome mutations deletion 1 , duplication 2 and inversion 3 . Image Two Chromosome Mutations.png thumb right The two major two chromosome mutations insertion 1 and Translocation 2 . A chromosome anomaly , abnormality or aberration reflects an atypical number of chromosome s or a structural abnormality in one or more chromosomes ... Karyotype for the species via genetic testing . A chromosome anomaly may be detected or confirmed in this manner. Chromosome anomalies usually occur when there is an error in cell division following meiosis or mitosis . There are many types of chromosome anomalies. They can be organized into two ... an abnormal number of chromosomes , and occurs when an individual is missing either a chromosome from ... an individual with Down Syndrome has three copies of chromosome 21, rather than two . Turner Syndrome is an example of a monosomy where the individual is born with only one sex chromosome, an X. Structural abnormalities When the chromosome s structure is altered. This can take several forms genetic deletion Deletions A portion of the chromosome is missing or deleted. Known disorders in humans include Wolf Hirschhorn syndrome , which is caused by partial deletion of the short arm of chromosome 4 ... A portion of the chromosome is duplicated, resulting in extra genetic material. Known human ... may be caused by duplication of the gene encoding peripheral myelin protein 22 PMP22 on chromosome 17. Chromosomal translocation Translocation s When a portion of one chromosome is transferred to another chromosome. There are two main types of translocations. In a reciprocal translocation, segments from two different chromosomes have been exchanged. In a Robertsonian translocation , an entire chromosome ..., 15, 21 and 22. Chromosomal inversion Inversions A portion of the chromosome has broken off, turned upside down and reattached, therefore the genetic material is inverted. Ring chromosome Rings A portion ... more details
Unreferenced auto yes date December 2009 The Satellite Chromosome is the chromosome which has a bulge on the telomeric end and contains the enzyme Sine Acido thymicio . Also referred to as SAT Chromosome, it plays a vital role in the formation of the nucleolous after division is completed. It shows repetitive sequences of genes Besides centromere , secondary constriction can also be observed in some chromosomes, which if present in the distal region of the arm, would pinch off a small fragment called Satellite . The satellite remains attached to the rest of the body of chromosome s by a thread of chromatin . The secondary constrictions are always constant in their positions and hence can be used as markers . The chromosomes having a satellite are marker chromosomes and are also called SAT chromosomes . DEFAULTSORT Satellite Chromosome Category Genetics Category Chromosomes Genetics stub pl Trabant biologia ... more details
Unreferenced stub auto yes date December 2009 Orphan date December 2009 Chromosome jumping is a tool of molecular biology that is used in the physical genome project mapping of genome s. It is related to several other tools used for the same purpose, including chromosome walking . Chromosome jumping is used to bypass regions difficult to cloning clone , such as those containing repetitive DNA , that cannot be easily mapped by chromosome walking, and is useful in moving along a chromosome rapidly in search of a particular gene . In chromosome jumping, the DNA of interest is identified, cut into fragments with restriction enzyme s, and circularised the beginning and end of each fragment are joined together to form a circular loop . From a known DNA sequence sequence a primer molecular biology primer is designed to DNA sequencing sequence across the circularised junction. This primer is used to jump 100 base pair kb 300 kb intervals a sequence 100 kb away would have come near the known sequence on circularisation. Thus, sequences not reachable by chromosome walking can be sequenced. Chromosome walking can be used from the new jump position in either direction to look for gene like sequences, or additional jumps can be used to progress further along the chromosome. DEFAULTSORT Chromosome Jumping Category Laboratory techniques Category Molecular biology Category DNA Molecular cell biology stub es Salto cromos mico fr Saut sur le chromosome ... more details
Unreferenced stub auto yes date December 2009 Dicentric chromosome is an aberrant chromosome having two centromere s. Dicentric chromosomes form when two chromosome segments from different chromosomes or from the two chromatids of a single one , each with a centromere, fuse end to end, with loss of their acentric fragments. Dicentrics, despite their two centromeres, may be mitotically stable if one of the two centromeres is inactivated, or if the two centromeres always coordinate their movement to one or the other pole during anaphase. Such chromosomes are formally called pseudodicentric. The most common pseudodicentrics involve the sex chromosomes or the acrocentric chromosomes Robertsonian translocation . Evaluation of centromere function by Fluorescent in situ hybridization FISH combined with immunofluorescence analysis of centromere and kinetochore proteins is a specialized procedure in some clinical cytogenetics laboratories. DEFAULTSORT Dicentric Chromosome Category Chromosomes Genetics stub ... more details
band of interest, and, using a very fine needle, tears that band away from the rest of the chromosome ... region of the chromosome in question. References Scalenghe F, Turco E, Edstrom JE, Pirrotta V, Melli ... more details
The genetics genetic technique of chromosome landing is a method of molecular cloning cloning of a gene of interest from a clone library . It is based on the principle that the expected average between genetic marker marker genetic distance distance s can be smaller than the average insert length of a clone library containing the gene of interest. From the abstract of PMID 7716809 The strategy of chromosome walking is based on the assumption that it is difficult and time consuming to find DNA markers that are physically close to a gene of interest. Recent technological developments invalidate this assumption for many species. As a result, the mapping paradigm has now changed such that one first isolates one or more DNA marker s at a physical distance from the targeted gene that is less than the average insert size of the genomic library being used for clone isolation. The DNA marker is then used to Genetic screen screen the library and isolate or land on the clone containing the gene, without any need for chromosome walking and its associated problems. Chromosome landing, together with the technology that has made it possible, is likely to become the main strategy by which map based cloning is applied to isolate both major genes and genes underlying quantitative traits in plant species. See also Primer walking Category Molecular biology Category Genetic engineering ... more details
Infobox disease Name Philadelphia chromosome Image Bcrablmet.jpg Caption A metaphase cell positive for the bcr abl rearrangement using Fluorescent in situ hybridization FISH DiseasesDB ICD10 ICD10 C 92 ... chromosome or Philadelphia translocation is a specific chromosome chromosomal abnormality ... translocation translocation between chromosome 9 and 22, and is specifically designated t 9 22 q34 ... on G banded chromosome preparations, or a variant translocation involving another chromosome ... Ph chromosome is not sufficiently Specificity tests specific to diagnose CML, since ..., Shah NP, Kantarjian H, et al. title Dasatinib in imatinib resistant Philadelphia chromosome positive ... chromosome is a Chromosomal translocation translocation . Parts of two chromosomes, 9 and 22, swap places. The result is that a fusion gene is created by juxtapositioning the Abl gene Abl1 gene on chromosome 9 region q34 to a part of the BCR gene BCR breakpoint cluster region gene on chromosome 22 region q11 . This is a reciprocal translocation, creating an elongated chromosome 9 der 9 , and an truncated chromosome 22 the Philadelphia chromosome . ref name pmid12755554 cite journal author Kurzrock R, Kantarjian HM, Druker BJ, Talpaz M title Philadelphia chromosome positive leukemias from basic ... fusion, located on the shorter derivative 22 chromosome. This gene encodes the Bcr abl fusion protein ... Blast crisis blast crisis in CML. Image Philadelphia chromosome.jpg Nomenclature Philadelphia chromosome is designated Ph or Ph chromosome and the translocation is termed t 9 22 q34.1 q11.2 . Therapy .... Citation needed date March 2011 History The Philadelphia chromosome was first discovered and described ... D. A minute chromosome in chronic granulocytic leukemia. Science journal Science 1960 132 ... D. Rowley at the University of Chicago identified the mechanism by which the Philadelphia chromosome .... Chromosomal translocation References reflist 2 External links MeshName Philadelphia chromosome Chromosomal ... more details
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