Gene redundancy is the existence of several genes in the genome of an organism that perform the same role to some extent. This is the case for many sets of paralogous genes. When an individual gene in such a set is disrupted by mutation or targeted gene knockout knockout , there can be little effect on phenotype as a result of gene redundancy, whereas the effect is large for double or triple gene knockouts. ref cite journal author P rez P rez JM, Candela H, Micol JL title Understanding synergy in genetic interactions journal Trends Genet. volume 25 issue 8 pages 368 76 year 2009 month August pmid 19665253 doi 10.1016 j.tig.2009.06.004 ref References reflist Further reading cite journal author Lehner B title Modelling genotype phenotype relationships and human disease with genetic interaction networks journal J Exp Biol volume 210 pages 1559 66 year 2007 pmid 17449820 doi 10.1242 jeb.002311 url http jeb.biologists.org cgi content full 210 9 1559 issue 9 DEFAULTSORT Gene Redundancy Category Genetics genetics stub ... more details
Orphan date April 2012 Mosaic analysis with a repressible cell marker , or MARCM, is a genetics technique for creating individually labeled homozygous cells in an otherwise heterozygous Drosophila melanogaster . ref name Trends in Neuroscience cite journal pmid 11311363 year 2001 last1 Lee first1 T last2 Luo first2 L title Mosaic analysis with a repressible cell marker MARCM for Drosophila neural development volume 24 issue 5 pages 251 4 journal Trends in neurosciences doi 10.1016 S0166 2236 00 01791 4 ref This technique relies on recombination during mitosis mediated by FLP FRT Recombination . As one copy of a gene, provided by the balancer chromosome , is often enough to rescue a mutant phenotype , MARCM clones can be used to study a mutant phenotype in an otherwise normal animal. See also Mosaic genetics References reflist Category Molecular genetics ... more details
The Mouse Phenome Database MPD is a web accessible database of strain biology strain characterization data for the laboratory mouse , to facilitate translational research for human health and disease. MPD characterizes phenotype as well as genotype , and provides tools for online analysis. Most phenotype data are in the form of strain surveys comparisons of 10 40 commonly used mouse strains and cover such areas as hematology , bone mineral density , cholesterol levels, endocrine function, and aging processes. Genotype data are primarily in the form of single nucleotide polymorphism s. Data are contributed by participating scientists or downloaded from public resources. ref Maddatu TP, Grubb SC, Bult CJ, Bogue MA. Mouse Phenome Database MPD . Nucleic Acids Res. 2012 Jan 40 Database issue D887 94. ref The MPD was begun in 2000, is funded by grants from the National Institutes of Health and other sources, and is headquartered at The Jackson Laboratory . References Reflist External links http phenome.jax.org Mouse Phenome Database Category Genetics Category Online databases Category Biological databases ... more details
Refimprove date December 2009 A phenocopy is an individual whose phenotype generally referring to a single Trait biological trait , under a particular environmental condition, is identical to the one of another individual whose phenotype is determined by the genotype . In other words the phenocopy environmental condition mimics the phenotype produced by a gene. The term was coined by Richard Goldschmidt in 1935 ref Goldschmidt. R., 1935. Gen und Ausseneigenschaft. I. Zeitschr. ind. Abstl. 69 38 69 ref . He used it to refer to forms, produced by some experimental procedure, whose appearance duplicates or copies the phenotype of some mutant or combination of mutants. A phenocopy is not a type of mutation, it is an environmentally induced, non hereditary phenotypic modification that resembles a similar phenotype produced by a gene mutation genocopy . An example of a phenocopy are the Vanessa genus of butterflies who can change phenotype based on the local temperature. If introduced to S pmi area Lapland they mimic butterflies localised to this area and if localised to Syria they mimic butterflies of this area. These phenotypes aren t inherited and are solely due to environment. Another great example is in Drosophila melanogaster . A variety of environmental factors produce abnormalities in these fruit flies that resemble the abnormal phenotypes of known genetic mutations. The environmental agents producing phenocopies includes temperature, shock, radiation, and various chemical compounds. In fruit fly, Drosophila melanogaster , the normal body colour is brownish gray with black margins. A hereditary mutant for this was discovered by Thomas Hunt Morgan T.H. Morgan in 1910 where the body colour is yellow. This was a genotypic character which was constant in both the flies in all environments. However, in 1939, Rapport discovered that if larva of normal flies were fed with silver salts, they develop into yellow bodied flies irrespective of their genotype Citation needed date ... more details
. A hypomorph is a reduction in gene protein, RNA expression, but not a complete loss. The phenotype ... protein activity. The phenotype of a hypermorph is worsened by increasing the wildtype gene dose, and is reduced ... of an antimorph, so the phenotype of an antimorph is worse when heterozygous than when in trans to a gene ... on the phenotype of a neomorph. m Df m m Dp Sources Muller, H. J. 1932. Further studies on the nature ... more details
who possess a phenotype of interest in a mutagenized population ref name McGraw Hartwell, L ... screen is an approach used to identify genes or set of genes responsible for a particular phenotype of an organism. Reverse genetics or a reverse genetic screen on the other hand, analyzes the phenotype of an organism following the disruption of a known gene. In short, forward genetics starts with a phenotype ... is performed to uncover every gene that is involved in a particular phenotype in a given species ... phenotype of interest. Enhancer Screen An enhancer screen begins with a mutant individual that has an affected .... A genetic enhancer screen identifies mutations which exacerbate or enhance a phenotype of interest in an already mutant individual. The phenotype of the double mutant individual with both the enhancer ... screen is used to identify suppressor mutations which alleviate or revert the phenotype of the original ... distinct from the mutation under study, which suppress the phenotype of the original mutation ref ... screen that involves temperature shifts to enhance the mutant phenotype. A population grown at low temperature would have a normal phenotype, however, the mutation in the particular gene would ... of a gene involved in the phenotype of interest. An advantage of alleles found in this type of screen is that the mutant phenotype is conditional and can be activated by simply raising the temperature ... cloning is a method of gene identification in which a gene for a specific phenotype is identified, with only ... recombination frequency compared to the mutant phenotype. When the DNA clone is at or close to the mutant ... compared to the mutant phenotype. Depending on the size of the mapping population, the mutant allele ... patterns consistent with the disease phenotype, showing a putative function related to the phenotype, or homologous to another gene linked to the phenotype are all priority candidates. Generalization ... more details
Forward genetics is an approach that encompasses several means of identifying the gene or set of genes that are responsible for a particular phenotype within an organism. Initially, this entailed the generation of random mutations in an organism, often through radiation or insertional mutagenesis ex. Sleeping Beauty transposon system Sleeping Beauty , and then through a series of breeding of subsequent generations, isolating individuals with an aberrant phenotype. Today there are many different means of following the general path of altering the genotype to observe the phenotype, several of which within the genomic era can be useful in the study of functional genomics . Forward genetics can be thought of as a counter to reverse genetics , which seeks to alter genes in order to illuminate their multiple phenotypes. Classical forward genetics By the classical genetics approach, a researcher would then locate map the gene on its chromosome by crossbreeding with individuals that carry other unusual traits and collecting statistics on how frequently the two traits are inherited together. Classical geneticists would have used phenotypic traits to map the new mutant alleles. Eventually the hope is that such screens would reach a large enough scale that most or all newly generated mutations would represent a second hit of a locus, essentially saturating the genome with mutations. This type of saturation mutagenesis within classical experiments was used to define sets of genes that were a bare minimum for the appearance of specific phenotypes. ref Greg Gibson and Spencer V. Muse. 2009. A Primer of Genome Science, Third Edition . Sinauer Press. ref However, such initial screens were either incomplete as they were missing redundant loci and epigenetic effects, and such screens were difficult to undertake for certain phenotypes that lack directly measurable phenotypes. Additionally a classical genetics approach takes significantly longer. References Reflist See also Reverse gen ... more details
PhenomicDB is a free phenotype oriented database . It contains data for some of the main model organisms such as Homo sapiens, Mus musculus, Drosophila melanogaster , and others. PhenomicDB merges and structures phenotypic data from various public sources WormBase , FlyBase , Entrez NCBI Gene , Mouse Genome Informatics MGI , and ZFIN using clustering algorithms. Further reading cite journal author Groth P, Kalev I, Kirov I, Traikov B, Leser U, Weiss B title Phenoclustering online mining of cross species phenotypes journal Bioinformatics journal Bioinformatics volume 26 issue 15 pages 1924 5 year 2010 month August pmid 20562418 pmc 2905556 doi 10.1093 bioinformatics btq311 url http bioinformatics.oxfordjournals.org cgi pmidlookup?view long&pmid 20562418 accessdate 2011 03 17 cite journal author Groth P, Pavlova N, Kalev I, Tonov S, Georgiev G, Pohlenz HD, Weiss B title PhenomicDB a new cross species genotype phenotype resource journal Nucleic Acids Research volume 35 issue Database issue pages D696 9 year 2007 month January pmid 16982638 pmc 1781118 doi 10.1093 nar gkl662 url http nar.oxfordjournals.org cgi pmidlookup?view long&pmid 16982638 accessdate 2011 03 17 cite journal author Kahraman A, Avramov A, Nashev LG, Popov D, Ternes R, Pohlenz HD, Weiss B title PhenomicDB a multi species genotype phenotype database for comparative phenomics journal Bioinformatics volume 21 issue 3 pages 418 20 year 2005 month February pmid 15374875 doi 10.1093 bioinformatics bti010 url http bioinformatics.oxfordjournals.org cgi pmidlookup?view long&pmid 15374875 accessdate 2011 03 17 cite doi 10.2174 157489306777828008 cite doi 10.1186 1471 2105 9 136 External links Official http www.phenomicdb.de Category Phenomics Category Biological databases ... more details
Helicobacter pylori virulence factor CagA cytotoxin associated gene A is a 120 145kDa protein encoded on the 40kb cag pathogenicity island PAI . ref name pmid16367902 cite journal author Hatakeyama, M. & Higashi, H. title Helicobacter pylori CagA a new paradigm for bacterial carcinogenesis journal Cancer Science volume 96 issue pages 835 843 year 2005 month pmid 16367902 doi 10.1111 j.1349 7006.2005.00130.x ref H. pylori strains can be divided into CagA positive or negative strains, of which around 60 of H. pylori isolates in Western countries are positive, whereas the majority of East Asian isolates are. ref name pmid16367902 The cag PAI also encodes for a Secretion type 4 secretion system which is used to inject CagA into a target cell upon H. pylori attachment. After translocation, CagA localises to the inner surface of the cell membrane and undergoes tyrosine phosphorylation by Src family kinase s e.g. FYN Fyn and LYN Lyn . ref name pmid16367902 Role in Cancer H. pylori infection is associated with MALT lymphoma and gastric adenocarcinoma and CagA is thought to be involved in cancer development. ref name pmid15806096 cite journal author Lax, A. title Bacterial toxins and cancer a case to answer? journal Nature Reviews Microbiology volume 3 issue pages 343 349 year 2005 month pmid 15806096 doi 10.1038 nrmicro1130 ref Phosphorylated CagA is able to interact with the PTPN11 SHP 2 tyrosine phosphatase , rendering it functionally active, triggering a host cell morphological change to a more motile phenotype known as the hummingbird phenotype . ref name pmid16367902 This phenotype mimics an effect produced by hepatocyte growth factor which may participate in various aspects of cancer, including metastasis . ref name pmid15806096 References reflist Category Virulence factors ... more details
PBB geneid 10 N acetyltransferase 2 arylamine N acetyltransferase , also known as NAT2 , is an enzyme which in humans is encoded by the NAT2 gene . ref name pmid7773298 cite journal author Vatsis KP, Weber WW, Bell DA, Dupret JM, Evans DA, Grant DM, Hein DW, Lin HJ, Meyer UA, Relling MV title Nomenclature for N acetyltransferases journal Pharmacogenetics volume 5 issue 1 pages 1 17 year 1995 month February pmid 7773298 doi 10.1097 00008571 199502000 00001 url issn ref Function This gene encodes a type of N acetyltransferase . The NAT2 isozyme functions to both activate and deactivate arylamine and hydrazine drugs and carcinogens. Polymorphisms in this gene are responsible for the N acetylation polymorphism in which human populations segregate into rapid, intermediate, and slow Drug metabolism Acetylation acetylator phenotype s. Polymorphisms in NAT2 are also associated with higher incidences of cancer and drug toxicity. A second arylamine N acetyltransferase gene NAT1 is located near NAT2. ref cite web title Entrez Gene NAT2 N acetyltransferase 2 arylamine N acetyltransferase url http www.ncbi.nlm.nih.gov sites entrez?Db gene&Cmd ShowDetailView&TermToSearch 10 accessdate ref Phenotype prediction The NAT2 acetylator phenotype can be inferred from NAT2 genotype a combination of Single nucleotide polymorphism SNP s observed in a given individual . ref name urlNAT2PRED a computational predictor of the human N AcetylTransferase 2 NAT2 acetylator phenotype cite web url http nat2pred.rit.albany.edu title NAT2PRED a computational predictor of the human N AcetylTransferase 2 NAT2 acetylator phenotype author authorlink coauthors date format work publisher State University of New York Albany pages language archiveurl archivedate quote accessdate 2009 04 30 ref ref name pmid19261719 cite journal author Kuznetsov IB, McDuffie M, Moslehi R title A web server for inferring the human N acetyltransferase 2 NAT2 enzymatic phenotype from NAT2 genotype journal Bioinformatics Oxford, En ... more details
are not the very rare hh antigen system Bombay phenotype which would require both parents ... or maternity disputes if tested by ABO blood grouping. Those of the above scenarios where a child s phenotype ... AB who will apparently look as a regular AB phenotype individual and an O individual will be either ... phenotype Hh and the child is a Bombay hh homozygous by genotype thus expressing Bombay phenotype ... more details
is a relationship between alleles of a gene , in which one allele masks the expression phenotype ... , and BB . If AA and BB individuals zygosity homozygotes show different forms of the trait phenotype , and AB individuals zygosity heterozygotes show the same phenotype as AA individuals, then allele ... to A . If instead AB has the same phenotype as BB , B is dominant to A . Background Diploid haploid ... affects its molecular, physical,and other traits, which individually or collectively are called the phenotype . At heterozygous gene loci, the two alleles interact to produce the phenotype. The simplest ... phenotype caused by one allele is apparent, called dominant, and the appearance phenotype ... effect of one allele completely masks the other in heterozygous combination that is, the phenotype produced ... Dominance refers to alleles that fully manifest their phenotype when present in the zygosity heterozygous ... of alleles in producing the phenotype of the heterozygote. If there are two alternative phenotypes, by definition the phenotype exhibited by the heterozygote is called dominant and the hidden phenotype ... in the phenotype. It is unrelated to the nature of the phenotype itself, e.g., whether it is regarded ..., and the round phenotype it produces. It is inaccurate to say that the round gene dominates ... the allele causing the round or wrinkled phenotype when homozygous is the dominant one. Another system ... different effects on the phenotype, and their dominance interactions with each other can be described ... Complete dominance occurs when the phenotype of the heterozygote is completely indistinguishable from ... Incomplete dominance occurs when the phenotype of the heterozygous genotype is an intermediate of the phenotypes ... of both alleles are visible in the phenotype. In the ABO example, the I sup A sup and I sup B sup allele classes are co dominant in producing the AB blood group phenotype, in which both A type and B type ... transcribed into RNA . Co dominance, where allelic products co exist in the phenotype, is different ... more details
Wiktionary robust Robustness may refer to In biology Robustness evolution , the persistence of a system s characteristic behavior under perturbations or conditions of uncertainty. According to the kind of perturbation involved, it can be classified as mutational robustness , environmental robustness , etc Mutational robustness , the extent to which an organism s phenotype remains constant in spite of mutation Robustness morphology Robust control Robust optimization Robust decision , a decision that is as immune to uncertainty as is possible and looks good to all constituents long after it is made Robust decision making Robust statistics , a statistical technique that performs well even if its assumptions are somewhat violated by the true model from which the data were generated Robustness computer science Robustness economics See also Fault tolerant system and links thereof Resilience disambiguation disambig fr Robustesse homonymie zh ... more details
Unreferenced date December 2009 Gene lethality occurs when two individuals of the same phenotype Mating mate and a 2 1 phenotypic ratio exists in the offspring as long as many offspring have been produced . Usually the homozygous dominant individuals will have been Abortion aborted before birth . The number of offspring in a Litter animal litter can also indicate whether gene lethality occurs. For example, on average, the litter size of a heterozygous x heterozygous cross will be less than a heterozygous x homozygous recessive cross if homozygous dominant is lethal. DEFAULTSORT Gene Lethality Category Classical genetics Genetics stub ... more details
Allele s have identity by type IBT when they have the same phenotype phenotypic effect , or if applied to a variation in the composition of DNA such as a Single nucleotide polymorphism when they have the same DNA sequence . Alleles that are identical by type fall into two groups those that are identical by descent IBD because they arose from the same allele in an earlier generation and those that are non identical by descent NIBD because they arose from separate mutation s. NIBD can also be identical by state IBS though, if they share the same mutational expression just not origin . Parent offspring pairs share 50 of their genes IBD, and monozygotic twins share 100 IBD. External links http darwin.eeb.uconn.edu eeb348 lecture notes identity.pdf http zwets.com pedkin thompson.pdf Category Classical genetics genetics stub ... more details
Unreferenced stub auto yes date December 2009 A candidate gene is a gene , located in a chromosome region suspected of being involved in the expression of a trait such as a disease, whose protein product suggests that it could be the gene in question. A candidate gene can also be identified by association with the phenotype and by linkage analysis to a region of the genome. A popular way to identify candidate genes is by microarray , this allows the researcher to analyse the expression levels of specific genes in a case control study, therefore if a gene is dysregulated in a disease it may be identified by microarray. However microarray has its weaknesses as it identifies all expression in the cell and could be reporting the expression of a gene which is affected by the disease rather than the cause. Qg DEFAULTSORT Candidate Gene Category Genetics Genetics stub de Kandidatengen fa nl Kandidaatgen ru ... more details
In psychology , a trait or phenotype is called emergenic if it is the result of a specific combination of several interacting gene s rather than of a simple sum of several independent genes . Emergenic traits will not run in families, but identical twin s will share them. Traits such as leadership , genius or certain mental illnesses may be emergenic. References Lykken DT, McGue M, Tellegen A, Bouchard TJ Jr. 1992 Emergenesis. Genetic traits that may not run in families. Am Psychol. 1992 Dec 47 12 1565 77. PMID 1476327 Category Genetics Category Emergence de Emergenesis ... more details
Threshold expression is a phenomenon in which phenotypic expression of a mitochondrial disease within an organ system occurs when the severity of the mutation, relative number of mutant mtDNA , and reliance of the organ system on oxidative phosphorylation combine in such a way that ATP production of the tissue falls below the level required by the tissue. The phenotype may be expressed even if the percentage of mutant mtDNA is below 50 if the mutation is severe enough. See also heteroplasmy References Marks basic medical biochemistry a clinical approach By Michael A. Lieberman, Michael Lieberman, Allan D. Marks Page 392 DEFAULTSORT Threshold Expression Category DNA Category Mitochondrial diseases biochem stub ... more details
Main Adaptation Climate adaptation refers to specific adaptations in a living organism that develop in response to changes in climate and habitat. Such adaptations could include physical changes, such as skin or fur color and composition changes, or the adaptations could be behavioral, such as burrowing into the ground or spending more time in water. See also Portal Evolutionary biology Evolution Evolutionary biology Climate change http www.safecoast.org Safecoast Knowledge exchange on coastal flooding and climate change in the North Sea region Melanism , in relation to industrial melanism References Reflist Category Evolution by phenotype evolution stub ... more details
Unreferenced stub auto yes date December 2009 Microbial genetics is a subject area within microbiology and genetic engineering . It studies the genetics of microorganism very small micro organisms . This involves the study of the genotype of microbial species and also the gene expression Expression system expression system in the form of phenotype s.It also involves the study of genetic processes taking place in these micro organisms i.e., recombination etc. See also http es.wikipedia.org w index.php?title Microbiolog C3 ADa&action edit§ion 3 A definition of microbial genetics in Spanish Wikipedia DEFAULT SORT Microbial Genetics Category Genetics Genetics stub hi ne ... more details
Lutheran antigen system is a Human blood group systems human blood group system based upon genes on chromosome 19 . This system is a single locus system, with antigens Lua and Lub. The Lu b negative phenotype is very rare. Antibodies to Lutheran antigens are IgG. The genes of the Lutheran group are linked to the genes responsible for the secretion of ABH substances. A complex blood group system having pairs of alternate antigens and amorphic genes, but also subject to a dominant independently segregating repressor. External links http www.ncbi.nlm.nih.gov projects mhc xslcgi.fcgi?cmd bgmut systems info&system lutheran Lutheran at BGMUT Blood Group Antigen Gene Mutation Database at National Center for Biotechnology Information NCBI , NIH transfusion medicine Category Blood antigen systems ... more details
protein name exostoses multiple 3 caption image width HGNCid 3514 Symbol EXT3 AltSymbols EntrezGene OMIM 600209 RefSeq UniProt PDB ECnumber Chromosome 19 Arm p Band LocusSupplementaryData EXT3 is a human gene. It is associated with hereditary multiple exostoses . ref name pmid11432960 cite journal author Francannet C, Cohen Tanugi A, Le Merrer M, Munnich A, Bonaventure J, Legeai Mallet L title Genotype phenotype correlation in hereditary multiple exostoses journal J. Med. Genet. volume 38 issue 7 pages 430 4 year 2001 month July pmid 11432960 pmc 1757186 doi 10.1136 jmg.38.7.430 url http jmg.bmj.com cgi pmidlookup?view long&pmid 11432960 ref References Reflist genetics stub ... more details
Orphan date November 2010 The xenia effect is the change caused in observable qualities phenotype of a seed as a result of the source of pollination , in addition to the change caused to the plant that the seed would grow into genotype . ref name Kuhlman cite web url http repository.tamu.edu handle 1969.1 2624 title Investigation of a xenia effect for yield caused by the waxy gene in grain sorghum author Kuhlman date 2005.08 work publisher Texas A&M University accessdate 12 November 2010 ref Qualities affected may include starchiness, sweetness, waxiness, or other aspects. References Reflist Agri stub Category Genetics ... more details
are heterozygous and share the same dominant phenotype 2 , while the F sub 2 sub generation ... of the dominant phenotype, of which two thirds are heterozygous, and a 25 chance for the appearance of the recessive phenotype. This cross was originally used by biologist, Gregor Mendel ... from the wrinkled parent . Because the round trait is dominant, the phenotype of all the seeds was round ... Rr both with the round phenotype and 25 rr with the wrinkled phenotype. class wikitable style text ... some of each phenotype in the F2 generation to self pollinate. His results All the wrinkled ... seeds in the F2 generation were homozygous and produced only seeds of the same phenotype ... phenotypes in the ratio of a typical F1 cross. Phenotype ratios are approximate The union of sperm ... where two different genotypes like RR and Rr produce the same phenotype. Mendel did not stop here ... more details
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