allele

[uh-leel] /əˈlil/

noun, Genetics.

any of several forms of a gene, usually arising through mutation, that are responsible for hereditary variation.

Origin

1930-35; < German Allel, apparently as shortening of German equivalents of allelomorph or allelomorphic gene; allelo- < Greek allēlo-, combining form of allḗlōn of/to one another, reciprocally

Related forms

allelic

[uh-lee-lik, uh-lel-ik] /əˈli lɪk, əˈlɛl ɪk/ (Show IPA), adjective

allelism, noun

interallelic, adjective

nonallelic, adjective

Examples from the web for alleles

Variation of alleles is critical to evolution, also known as the reason we're here.
Traditional laboratory mice have a limited number of alleles-that is, different versions of the same gene.
Biological evolution consists of nothing more than a change in the frequency of alleles in a breeding population.
In this way genetic diversity of even deleterious alleles can be preserved as many low frequency recessively expressed variants.
Having totally different alleles for a gene can have absolutely no effect if the gene is not expressed.
But, you never know what will happen when you mix alleles from different genetic backgrounds.
For each of the three, there are thousands of different versions, or alleles.
As the population size increases, however, the total number of alleles becomes more or less restricted to moving by one.
Functional testing of variant alleles has begun to connect phenotype correlations with biological differences.
Every human has a suite of deleterious alleles, some of them inherited from their parents, some of them new and unique.

British Dictionary definitions for alleles

allele

/əˈliːl/

noun

any of two or more variants of a gene that have the same relative position on homologous chromosomes and are responsible for alternative characteristics, such as smooth or wrinkled seeds in peas Also called allelomorph (əˈliːləˌmɔːf) See also multiple alleles

Derived Forms

allelic, adjective
allelism, noun

Word Origin

C20: from German Allel, shortened from allelomorph, from Greek allēl- one another + morphē form

Word Origin and History for alleles

allele

1931, from German allel, abbreviation of allelomorph (1902), coined from Greek allel- "one another" (from allos "other;" see alias) + morphe "form" (see Morpheus).

alleles in Medicine

allele al·lele (ə-lēl')
n.
One member of a pair or series of genes that occupies a specific position on a specific chromosome. Also called allelomorph.

al·le'lic (ə-lē'lĭk, ə-lěl'ĭk) adj.

alleles in Science

allele

(ə-lēl')
Any of the possible forms in which a gene for a specific trait can occur. In almost all animal cells, two alleles for each gene are inherited, one from each parent. Paired alleles (one on each of two paired chromosomes) that are the same are called homozygous, and those that are different are called heterozygous. In heterozygous pairings, one allele is usually dominant, and the other recessive. Complex traits such as height and longevity are usually caused by the interactions of numerous pairs of alleles, while simple traits such as eye color may be caused by just one pair.

alleles in Culture

allele [(ul-leel)]

The sequence of nucleotides on a DNA molecule that constitutes the form of a gene at a specific spot or a chromosome. There can be several variations of this sequence, and each of these is called an allele. In the case of the gene for eye color, for example, one allele codes for blue eyes, whereas the other may code for brown eyes.