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Any of the alternative forms of a gene or other homologous DNA sequence. Also called allelomorph.

[German Allel, short for Allelomorph, allelomorph, from English allelomorph.]

al·le′lic (ə-lē′lĭk, ə-lĕl′ĭk) adj.
al·le′lism n.


(əˈliːl) or


(Genetics) 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 See also multiple alleles
[C20: from German Allel, shortened from allelomorph, from Greek allēl- one another + morphē form]
alˈlelic adj
alˈlelism n



one of two or more alternative forms of a gene occupying the same position on matching chromosomes: an individual normally has two alleles for each trait, one from either parent.
[1930–35; < German Allel, appar. as shortening of German equivalents of allelomorph or allelomorphic gene]
al•lel•ic (əˈli lɪk, əˈlɛl ɪk) adj.
al•lel′ism, n.


Any of the possible forms in which a gene for a specific trait can occur. In almost all animal cells, two alleles for each trait are inherited, one from each parent. Alleles on each of a pair of chromosomes are called homozygous if they are similar to each other and heterozygous if they are different.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.allele - (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 characterallele - (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"
cistron, gene, factor - (genetics) a segment of DNA that is involved in producing a polypeptide chain; it can include regions preceding and following the coding DNA as well as introns between the exons; it is considered a unit of heredity; "genes were formerly called factors"
dominant allele, dominant - an allele that produces the same phenotype whether its paired allele is identical or different
recessive, recessive allele - an allele that produces its characteristic phenotype only when its paired allele is identical
genetic science, genetics - the branch of biology that studies heredity and variation in organisms


n. alelo, alelomorfo, uno de dos o más genes de una serie que ocupa la misma posición en cromosomas homólogos y que determina características alternantes en los descendientes.
References in periodicals archive ?
2007) software on the basis of all adult individual's genotypes (without recapture individuals, n = 77): deviation from Hardy-Weinberg equilibrium, observed and expected heterozygosity and a null allele (i.
2,3) IR8 contains a 383-bp deletion from exon 1 to exon 2 in SD-1, which produces a null allele carrying a premature stop codon.
taylori) did not have enough data to calculate null allele frequencies Subspecies Locus n [n.
For those markers where departures from Mendelian expectation occurred, the family group exhibited a potential null allele or an unexpected band was observed, both parents and 6 progeny were selected and DNA amplified.
Leu55Met (SM) Pesticides CYP2D6 rs3892097 G>A, null allele (PM) Pesticides CYP2D6 rs3892097 G>A, null allele (PM) Caffeine CYP1A2 rs762551 C>A rs2470890 C>T, p.
Identification of a null allele at the Wx-B1 locus in some of Iranian bread wheat genotypes, Advances in Environmental Biology, 6(10): 2586-2589.
The results of the analysis of polymorphisms in GSTM1 and GSTT1 indicated that there was a higher incidence of the GSTM1 null allele of 66.
Wx-B1 null allele indicates reduced amylase (Briney et al.
A third reason for an inconclusive CLR can be the transmission of a null allele from parent to child.
The null allele CSN1S2 O associated with a non-detectable amount of this casein fraction shows a G- A transition at the 80th nucleotide in exon 11, creating a premature stop codon at position 110 (Ramunno et al.
DT104o was specific for the DT104 group, and all 100 DT104 group isolates displayed amplified products with 13-40 repeat copy numbers; the others showed the null allele.