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.
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.
First recorded in 1911; from German Gen (1909), apparently abstracted from -gen -gen ( def. ); introduced by Danish geneticist Wilhelm L. Johannsen (1857–1927)
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.
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This is the same gene that is mutated in people with FPLD2.
From Science Daily ● Jul. 26, 2026
Mr. Woolfson also lingers admiringly on Har Gobind Khorana, a village clerk’s son in British India who went on to synthesize the first fully artificial gene in 1972.
From The Wall Street Journal ● Jul. 24, 2026
Part of the difficulty has to do with gene sequencing, he explained.
From BBC ● Jul. 24, 2026
APOE2 neurons had significantly less DNA damage than neurons carrying the other gene variants.
From Science Daily ● Jul. 24, 2026
The atom, the byte, and the gene provide fundamentally new scientific and technological understandings of their respective systems.
From "The Gene" by Siddhartha Mukherjee
While Mr. Richman’s vocals retained punk’s nasal, monochromatic tone, his songs were dorky and witty, channeling Buddy Holly, Gene Vincent and Freddie and the Dreamers.
From The Wall Street Journal ● Jul. 22, 2026
Billy Gene Mills was elected to the Los Angeles City Council in 1963 and served until 1974.
From Los Angeles Times ● Jul. 16, 2026
Gene Lanzoni rose up through the ranks in the insurance industry while taking care of his wife, who had breast cancer, as well as his aging parents and in-laws during different periods of his career.
From MarketWatch ● Jul. 7, 2026
Memorable cinematic roles have included a corrupt police officer in the Harrison Ford thriller "Witness" and a comedy turn in Wes Anderson's eccentric "The Royal Tenenbaums," opposite Gene Hackman.
From Barron's ● Jul. 1, 2026
Gene looks surprised that I’m approaching him—and calmly too.
From "Popcorn" by Rob Harrell
Coupled with abundant haplotype diversity, tetraploid potato may therefore contain thousands of -gene analogues.
From Nature ● Jul. 13, 2011
Longevity prospered because these fit, caring and longer-lived grandmothers passed along their genes to more grandchildren.
From The Wall Street Journal ● Jul. 28, 2026
Instead, they appeared especially often in genes involved in immune function and olfaction, or the sense of smell.
From Science Daily ● Jul. 26, 2026
Being born with good genes and not abusing them, along with remaining active can be a big plus.
From The Wall Street Journal ● Jul. 25, 2026
For example, humans carry the genes needed to produce these specialized touch-sensitive neurons.
From Science Daily ● Jul. 14, 2026
The mathematics to model a trait controlled by five or seven genes, Fisher discovered, was not all that complex.
From "The Gene" by Siddhartha Mukherjee
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
