heterozygous

American  

[het-er-uh-zahy-guhs] / ˌhɛt ər əˈzaɪ gəs /

Also heterozygotic

adjective

Genetics.

1. relating to or being a heterozygote, an organism that possesses a pair of differing alleles, one dominant and one recessive, of a particular gene.

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heterozygous British  

/ ˌhɛtərəʊˈzaɪɡəs /

adjective

1. genetics (of an organism) having different alleles for any one gene Compare homozygous

   heterozygous for eye colour

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heterozygous Scientific  

/ hĕt′ər-ə-zī′gəs /

1. Relating to a cell that has two different alleles at corresponding positions on homologous chromosomes.

2. Compare homozygous

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Other Word Forms

• heterozygosity
  noun

Etymology

Origin of heterozygous

First recorded in 1900–05; hetero- + Greek zygós, adjective derivative of zygón “yolk”; see -ous

Explanation

Genes come in pairs, called alleles, and each pair is located in a specific position (or locus) on a chromosome. If the two alleles at a locus are identical to each other, they are homozygous; if they are different from one another, they are heterozygous. Like all words with the prefix hetero, heterozygous has to do with things that are different — specifically genes. When alleles are heterozygous they are unalike in some way. Alleles determine the genotype, or genetic structure, of a specific gene. For example, you may have received the allele for brown eyes from your mom and the allele for blue eyes from your dad; that means that you are heterozygous for eye color. Whether an organism's genotype is heterozygous or homozygous helps to determine its appearance (which is called its phenotype).

Example Sentences

He hopes that physicians add this gene to the list of lupus-associated genes, "so if they see a mutation like these, even a heterozygous mutation, they will investigate further."

From Science Daily • May 23, 2024

Both parents are heterozygous, having the green trait on the green-blue eye gene.

From Textbooks • Jun. 9, 2022

In contrast, a cross between AABb and AABb has an n of 1 because A is not heterozygous.

From Textbooks • Jun. 9, 2022

When P plants with contrasting traits were cross-fertilized, all of the offspring were heterozygous for the contrasting trait, meaning their genotype had different alleles for the gene being examined.

From Textbooks • Apr. 25, 2013

This at once suggests that the black and the splashed white are the two homozygous forms, and that the blues are heterozygous, i.e., producing equal numbers of "black" and "white splashed" gametes.

From Mendelism Third Edition by Punnett, Reginald Crundall