gene

¹ American  

[jeen] / dʒin /

noun

1. the basic physical unit of heredity; a linear sequence of nucleotides along a segment of DNA that provides the coded instructions for synthesis of RNA, which, when translated into protein, leads to the expression of hereditary character.

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Gene ² American  

[jeen] / dʒin /

noun

1. a male given name, form of Eugene.

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-gene ¹ British  

suffix

1. a variant of -gen

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gene ² British  

/ dʒiːn /

noun

1. a unit of heredity composed of DNA occupying a fixed position on a chromosome (some viral genes are composed of RNA). A gene may determine a characteristic of an individual by specifying a polypeptide chain that forms a protein or part of a protein ( structural gene ); or encode an RNA molecule; or regulate the operation of other genes or repress such operation See also operon

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gene Scientific  

/ jēn /

1. A segment of DNA, occupying a specific place on a chromosome, that is the basic unit of heredity. Genes act by directing the production of RNA, which determines the synthesis of proteins that make up living matter and are the catalysts of all cellular processes. The proteins that are determined by genetic DNA result in specific physical traits, such as the shape of a plant leaf, the coloration of an animal's coat, or the texture of a person's hair. Different forms of genes, called alleles, determine how these traits are expressed in a given individual. Humans are thought to have 20,000 to 25,000 genes; bacteria have between 500 and 6,000.

2. See also dominant recessive See Note at Mendel

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gene Cultural  

1. A portion of a DNA molecule that serves as the basic unit of heredity. Genes control the characteristics that an offspring will have by transmitting information in the sequence of nucleotides on short sections of DNA.

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Usage

What is a gene? A gene is a sequence of nucleotides along a strand of DNA that a cell nucleus uses to produce proteins. Genes determine the specific traits of an organism. DNA (deoxyribonucleic acid) is a large molecule that is shaped like a double helix sometimes described as a twisty ladder. The rungs of the ladder are made of molecules called nucleotides. These rungs, or bases, are arranged in a specific order that creates a set of instructions, which is known as a gene. When the body needs to do something or build something, it often requires a protein. Genes are the instructions that the cells read for how to build proteins. Proteins have very specific jobs, so scientists name genes based on what job their linked proteins are designed to do. For example, hair proteins come from hair genes, while eye proteins come from eye genes. Every living organism has genes. Animals, plants, fungi, bacteria, and even the humble amoeba all have genes. The more closely related two organisms are, the more similar their genes will be. For example a dog and a wolf, which are from the same genus, will have similar genes, while a dog and a human, which are not part of the same genus, will have much different genes from each other.

Etymology

Origin of gene

First recorded in 1911; from German Gen (1909), apparently abstracted from -gen -gen ( def. ); introduced by Danish geneticist Wilhelm L. Johannsen (1857–1927)

Explanation

Microscopic, yet powerful, a gene is segment of DNA, the molecule that stores the code for building living bodies. A gene is a single unit of genetic information, stored on twisting strands in every cell of every living being. In sexual reproduction, the parents' genes mix together to make the child. Although people would like to think that genes code for discrete traits, like friendliness or mathematical genius, that's not the case. Genes control the color of your eyes and the shape of your toes, not your weird personality.

Example Sentences

"A bacterial CARD-NLR-like immune system controls the release of gene transfer agents," appears in Nature Microbiology.

From Science Daily • Apr. 17, 2026

This process, called horizontal gene transfer, allows bacteria to quickly share useful traits, including genes that help them survive antibiotic treatments.

From Science Daily • Apr. 17, 2026

That is because in 2024 it was revealed that the so-called "next Berlin patient" entered long-term remission despite receiving a transplant that did not have two copies of the mutated gene.

From Barron's • Apr. 13, 2026

The high-risk procedure normally requires a donor to have a specific mutation of their CCR5 gene, which blocks HIV from entering the body's cells.

From Barron's • Apr. 13, 2026

Now everyone was checked for the gene at birth.

From "Glitch" by Laura Martin