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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They examined human brain tissue and cerebrospinal fluid, the clear liquid surrounding the brain and spinal cord, using genetic and epigenetic analyses to explore changes in DNA and gene activity.
From Science Daily ● Oct. 19, 2026
Insignum uses gene editing to “switch on” traits already within the plant’s DNA.
From The Wall Street Journal ● Oct. 19, 2026
The gene is usually carried into the cells by a virus that has been altered so that it cannot cause disease.
From Science Daily ● Oct. 19, 2026
A handful of startups are using gene editing and sensors to do just that, programming plants to “tell” farmers when they are under stress before visible symptoms appear.
From The Wall Street Journal ● Oct. 19, 2026
The gene molecule had to somehow look like a gene molecule.
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
Gene Wilder's voice was recreated using AI in the new show, which Goffe said was "magical"
From BBC ● Sep. 23, 2026
Gene activity also revealed improvements in several biological features associated with aging, including reduced inflammation and less decline in the body's ability to repair and regenerate tissue.
From Science Daily ● Sep. 12, 2026
Gene therapy has offered a more promising path.
From The Wall Street Journal ● Sep. 9, 2026
Gene returned from Florida and they were married.
From "Educated" by Tara Westover
Coupled with abundant haplotype diversity, tetraploid potato may therefore contain thousands of -gene analogues.
From Nature ● Jul. 13, 2011
Shely Aronov, chief executive of California startup InnerPlant, explains that when plants are attacked they start to activate genes to protect themselves.
From The Wall Street Journal ● Oct. 19, 2026
This approach allowed them to search for genes that might produce enzymes capable of breaking apart plastic polymers.
From Science Daily ● Oct. 16, 2026
The researchers also discovered that the expression of genes responsible for autophagy did not reliably indicate how much recycling was actually occurring.
From Science Daily ● Oct. 13, 2026
This analysis allowed them to examine how age and cell type affected the activity of genes involved in autophagy.
From Science Daily ● Oct. 13, 2026
In the 1980s, human geneticists begin to use these techniques to map and identify genes linked to diseases, such as Huntington’s disease and cystic fibrosis.
From "The Gene" by Siddhartha Mukherjee
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