allele

アレル 　 　

WordNet

1. (genetics) either of a pair (or series) of alternative forms of a gene that can occupy the same locus on a particular chromosome and that control the same character; "some alleles are dominant over others" (同)allelomorph
2. of or relating to alleles (同)allelomorphic
3. the univalent unsaturated organic radical C3H5; derived from propylene (同)allyl_group, allyl radical
4. of or pertaining to the allyl radical
5. a prism whose bases are parallelograms (同)parallelopiped, parallelepipedon, parallelopipedon
6. an allele that produces its characteristic phenotype only when its paired allele is identical (同)recessive
7. genes that are not competitors at the same locus

PrepTutorEJDIC

1. 対立遺伝子(通例突然変異によって生じる)
2. 平行六面体
3. 並ぶもののない,比類(前例)のない

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2012/11/23 20:14:53」(JST)

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This article is about the forms of a gene. For a non-technical introduction to the topic, see Introduction to genetics. For the alternative metal band, see Allele (band).

An allele (UK  /ˈæliːl/ or US /əˈliːl/) is one of two or more forms of a gene or a genetic locus (generally a group of genes). The form "allel" is also used, an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation. However, many variations at the genetic level result in little or no observable variation.

Most multicellular organisms have two sets of chromosomes, that is, they are diploid. These chromosomes are referred to as homologous chromosomes. Diploid organisms have one copy of each gene (and therefore one allele) on each chromosome. If both alleles are the same, they are homozygotes. If the alleles are different, they are heterozygotes.

A population or species of organisms typically includes multiple alleles at each locus among various individuals. Allelic variation at a locus is measurable as the number of alleles (polymorphism) present, or the proportion of heterozygotes in the population.

For example, at the gene locus for the ABO blood type carbohydrate antigens in humans, classical genetics recognizes three alleles, I^A, I^B, and I^O, that determine compatibility of blood transfusions. Any individual has one of six possible genotypes (AA, AO, BB, BO, AB, and OO) that produce one of four possible phenotypes: "A" (produced by AA homozygous and AO heterozygous genotypes), "B" (produced by BB homozygous and BO heterozygous genotypes), "AB" heterozygotes, and "O" homozygotes. It is now known that each of the A, B, and O alleles is actually a class of multiple alleles with different DNA sequences that produce proteins with identical properties: more than 70 alleles are known at the ABO locus. An individual with "Type A" blood may be an AO heterozygote, an AA homozygote, or an A'A heterozygote with two different 'A' alleles.

The word "allele" is a short form of allelomorph ('other form'), which was used in the early days of genetics to describe variant forms of a gene detected as different phenotypes. It derives from the Greek root ἄλλος, and alius (Latin) meaning "other"; then the word αλληλους, allelos, meaning "each other".

Dominant and recessive alleles

In many cases, genotypic interactions between the two alleles at a locus can be described as dominant or recessive, according to which of the two homozygous genotypes the phenotype of the heterozygote most resembles. Where the heterozygote is indistinguishable from one of the homozygotes, the allele involved is said to be dominant to the other, which is said to be recessive to the former. The degree and pattern of dominance varies among loci. For a further discussion see Dominance (genetics). This type of interaction was first formally described by Gregor Mendel. However, many traits defy this simple categorisation and the phenotypes are modeled by polygenic inheritance.

The term "wild type" allele is sometimes used to describe an allele that is thought to contribute to the typical phenotypic character as seen in "wild" populations of organisms, such as fruit flies (Drosophila melanogaster). Such a "wild type" allele was historically regarded as dominant, common, and "normal", in contrast to "mutant" alleles regarded as recessive, rare, and frequently deleterious. It was commonly thought that most individuals were homozygous for the "wild type" allele at most gene loci, and that any alternative 'mutant' allele was found in homozygous form in a small minority of "affected" individuals, often as genetic diseases, and more frequently in heterozygous form in "carriers" for the mutant allele. It is now appreciated that most or all gene loci are highly polymorphic, with multiple alleles, whose frequencies vary from population to population, and that a great deal of genetic variation is hidden in the form of alleles that do not produce obvious phenotypic differences.

Allele and genotype frequencies

The frequency of alleles in a diploid population can be used to predict the frequencies of the corresponding genotypes (see Hardy-Weinberg principle). For a simple model, with two alleles:

where p is the frequency of one allele and q is the frequency of the alternative allele, which necessarily sum to unity. Then, p² is the fraction of the population homozygous for the first allele, 2pq is the fraction of heterozygotes, and q² is the fraction homozygous for the alternative allele. If the first allele is dominant to the second, then the fraction of the population that will show the dominant phenotype is p² + 2pq, and the fraction with the recessive phenotype is q².

With three alleles:

and

In the case of multiple alleles at a diploid locus, the number of possible genotypes (G) with a number of alleles (a) is given by the expression:

Allelic variation in genetic disorders

A number of genetic disorders are caused when an individual inherits two recessive alleles for a single-gene trait. Recessive genetic disorders include Albinism, Cystic Fibrosis, Galactosemia, Phenylketonuria (PKU), and Tay-Sachs Disease. Other disorders are also due to recessive alleles, but because the gene locus is located on the X chromosome, so that males have only one copy (that is, they are hemizygous), they are more frequent in males than in females. Examples include red-green color blindness and Fragile X syndrome.

Other disorders, such as Huntington disease, occur when an individual inherits only one dominant allele.

See also

• Allozyme
• Evolution
• Genealogical DNA test
• Haplo-sufficiency
• Meiosis
• Mendelian error
• Mendelian inheritance
• Mitosis
• Polymorphism
• Punnett square

References and notes

• National Geographic Society, Alton Biggs, Lucy Daniel, Edward Ortleb, Peter Rillero, Dinah Zike. "Life Science". New York, Ohio, California, Illinois: Glencoe McGraw-Hill. 2002

External links

• ALFRED: The ALlele FREquency Database
• EHSTRAFD.org - Earth Human STR Allele Frequencies Database

UpToDate Contents

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English Journal

• Introgression of Brown Norway CYP4A genes on to the Dahl salt-sensitive background restores vascular function in SS-5BN consomic rats.

• Lukaszewicz KM, Falck JR, Manthati VL, Lombard JH.Source*Department of Physiology, Medical College of Wisconsin, Milwaukee, WI 53226, U.S.A.
• Clinical science (London, England : 1979).Clin Sci (Lond).2013 Mar 1;124(5):333-42. doi: 10.1042/CS20120232.
• The present study tested the hypothesis that the Dahl SS (salt-sensitive) rat has vascular dysfunction due, in part, to the up-regulation of the CYP4A/20-HETE (cytochrome P450 ω-hydroxylase 4A)/20-hydroxyeicosatetraenoic acid) system. To assess the role of vascular 20-HETE, SS rats were compared wi
• PMID 22938512

• Trypanosoma cruzi carrying a monoallelic deletion of the calreticulin (TcCRT) gene are susceptible to complement mediated killing and defective in their metacyclogenesis.

• Sánchez Valdéz FJ, Pérez Brandán C, Zago MP, Labriola C, Ferreira A, Basombrío MÁ.SourceInstituto de Patología Experimental - CONICET, Universidad Nacional de Salta, Salta, Argentina. fersanchez80@hotmail.com
• Molecular immunology.Mol Immunol.2013 Mar;53(3):198-205. doi: 10.1016/j.molimm.2012.08.001. Epub 2012 Sep 3.
• Trypanosoma cruzi calreticulin (TcCRT) can hijack complement C1, mannan-binding lectin and ficolins from serum thus inhibiting the classical and lectin complement pathway activation respectively. To understand the in vivo biological functions of TcCRT in T. cruzi we generated a clonal cell line lack
• PMID 22954747

• Proinflammatory cytokine IL-1 β polymorphisms in sudden sensorineural hearing loss.

• Um JY, Jang CH, Kim HL, Cho YB, Park J, Lee SJ, Kim YB, Kim HJ, Ahn KS, Jang HJ, Lee SG, Lee H, Lee KM, Kim SJ, Hong SH.SourceCollege of Korean Medicine, Institute of Korean Medicine, Kyung Hee University , 1 Heogi-dong, Dongdaemun-gu, Seoul , Republic of Korea.
• Immunopharmacology and immunotoxicology.Immunopharmacol Immunotoxicol.2013 Feb;35(1):52-6. doi: 10.3109/08923973.2012.719523. Epub 2012 Sep 26.
• The cause and pathogenesis of sudden sensorineural hearing loss (SSNHL) remain unknown. IL-1β is one of the most powerful inflammatory cytokines. The aim of this study was to evaluate the relationships between interleukin-1 β (IL-1β) gene polymorphisms (-511 C/T and +3953 C/T) in patients with SS
• PMID 23013363

Japanese Journal

• Non-pungency in a Japanese Chili Pepper Landrace (Capsicum annuum) is Caused by a Novel Loss-of-function Pun1 Allele

• The Horticulture Journal advpub(0), 2018
• NAID 130005153886

• 本態性血小板血症におけるMPL W515L/K遺伝子変異検出法の比較検討

• 天理医学紀要 = Tenri medical bulletin 19(1・2), 51-57, 2016-12
• NAID 40021044064

• Oral Administration of Apple Procyanidins Ameliorates Insulin Resistance via Suppression of Pro-inflammatory Cytokines Expression in Liver of Diabetic ob/ob Mice

• Journal of Agricultural and Food Chemistry 64(46), 8857-8865, 2016-11-23
• NAID 120005893547

• RNF213 rare variants in Slovakian and Czech moyamoya disease patients

• PLOS ONE 11(10), 2016-10-13
• NAID 120005853279

Related Links

• Allele | Define Allele at Dictionary.com - Dictionary.com | Find ...

Allele definition, any of several forms of a gene, usually arising through mutation, that are responsible for hereditary variation. See more. ... any of two or more variants of a gene that have the same relative position on homologous ...

• Alleleとは - goo Wikipedia (ウィキペディア)

The frequency of alleles in a diploid population can be used to predict the frequencies of the corresponding genotypes (see Hardy-Weinberg principle). For a simple model, with two alleles: where p is the frequency of one allele and q is ...

• Alleles | definition of Alleles by Medical dictionary

It is interesting that only two CSN1S2 alleles (A and F allele) were detected in two Chinese dairy goat breeds in the present study, which is greatly different from the CSN1S2 allelic distribution in European dairy goat breeds.

Related Pictures

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★リンクテーブル★

リンク元	「allelic」「対立遺伝子」「アリル」「allelomorph」「アレル」
拡張検索	「mutant allele」「allele specific oligonucleotide」

「allelic」

　　[★]

• adj.

• 対立形質の、対立遺伝子の

関

allele、allelic character、allelomorph、allelomorphic、allelotype

　

「対立遺伝子」

　　[★]

英

allele

同

アレル、アリル、アリール

関

遺伝子、ハプロタイプ、複対立遺伝子

「アリル」

　　[★]

英

(化学)allyl、allylic、(遺伝)allele

関

対立遺伝子、アレル、アレレ

「allelomorph」

　　[★]

• 対立形質

関

allele、allelic、allelic character、allelomorphic、allelotype

「アレル」

　　[★]

英

allele

関

アリル、対立遺伝子、アレレ

「mutant allele」

　　[★]

• 変異誘発遺伝子、突然変異遺伝子

関

mutator gene

「allele specific oligonucleotide」

　　[★] アレル特異的オリゴヌクレオチド ASO