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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Further analysis revealed that the gene produces an esterase, a type of enzyme capable of splitting certain chemical bonds found in esters.
From Science Daily ● Oct. 16, 2026
The two unacquainted orphans sign up, conscious that they have inherited the larceny gene and, unconsciously perhaps, craving a family.
From The Wall Street Journal ● Oct. 15, 2026
As part of the testing, it was revealed that she had gene mutations that increased her risk of breast and ovarian cancer.
From BBC ● Oct. 14, 2026
Menin also participates in regulating gene activity, allowing it to influence multiple biological pathways.
From Science Daily ● Oct. 12, 2026
As new flies had been born, selected, and bred, the gene frequencies had changed, resulting in populations with new genetic compositions.
From "The Gene" by Siddhartha Mukherjee
The Roadster demo “was an engineering flex with no commercial value beyond embarrassing traditional car makers,” Gene Munster, managing partner at Deepwater Asset Management, wrote on X.
From MarketWatch ● Oct. 16, 2026
Not long after, Gene Kirkwood, who worked for the producers, called to tell me a director named John Avildsen was interested.
From The Wall Street Journal ● Sep. 24, 2026
Rusty Goffe began his film career in the Gene Wilder movie, before later appearing in the original Star Wars, the Harry Potter films and Doctor Who.
From BBC ● Sep. 23, 2026
Rod Roddenberry, founder of the Roddenberry Foundation and son of “Star Trek” creator Gene Roddenberry and actor Majel Barrett Roddenberry, is an executive producer on current “Star Trek” television shows.
From Los Angeles Times ● Sep. 22, 2026
Farm life had made Gene different from other young men: he was serious for his age, more physically impressive and independent-minded.
From "Educated" by Tara Westover
Coupled with abundant haplotype diversity, tetraploid potato may therefore contain thousands of -gene analogues.
From Nature ● Jul. 13, 2011
He then sequenced the genetic material and carefully analyzed the extensive data to determine which microbes and genes became especially abundant as the bioplastics decomposed.
From Science Daily ● Oct. 16, 2026
A screening service operates in Northern Ireland to provide testing for family members of people who have FH to detect as many carriers of the genes as possible.
From BBC ● Oct. 13, 2026
These newly formed connections changed how genes could interact and be controlled, potentially helping drive the evolution of the unusually complex nervous systems found in these animals, which are collectively known as coleoid cephalopods.
From Science Daily ● Oct. 12, 2026
The emergence of extraordinary traits may depend not only on which genes an organism inherits, but also on how those genes are physically arranged and connected within the cell.
From Science Daily ● Oct. 12, 2026
If genes were, indeed, independent particles of information, then it should be possible to select, purify, and manipulate these particles independently from one another.
From "The Gene" by Siddhartha Mukherjee
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