mutation

American  

[myoo-tey-shuhn] / mjuˈteɪ ʃən /

noun

mutations plural

1. Biology.

   1. Also called break.  a sudden departure from the parent type in one or more heritable characteristics, caused by a change in a gene or a chromosome.

   2. Also called sport.  an individual, species, or the like, resulting from such a departure.

2. the act or process of changing.

3. a change or alteration, as in form or nature.

4. Phonetics. umlaut.

5. Linguistics. (in Celtic languages) syntactically determined morphophonemic phenomena that affect initial sounds of words.

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mutation British  

/ mjuːˈteɪʃən /

noun

1. the act or process of mutating; change; alteration

2. a change or alteration

3. a change in the chromosomes or genes of a cell. When this change occurs in the gametes the structure and development of the resultant offspring may be affected See also inversion

4. another word for mutant

5. a physical characteristic of an individual resulting from this type of chromosomal change

6. phonetics

   1. (in Germanic languages) another name for umlaut

   2. (in Celtic languages) a phonetic change in certain initial consonants caused by a preceding word

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mutation Scientific  

/ myo̅o̅-tā′shən /

1. A change in the structure of the genes or chromosomes of an organism. Mutations occurring in the reproductive cells, such as an egg or sperm, can be passed from one generation to the next. Most mutations occur in junk DNA and have no discernible effects on the survivability of an organism. Of the remaining mutations, the majority have harmful effects, while a minority can increase an organism's ability to survive. A mutation that benefits a species may evolve by means of natural selection into a trait shared by some or all members of the species.

2. See Note at sickle cell anemia

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Other Word Forms

Derived Forms

• mutational
  adjective
• nonmutational
  adjective
• unmutational
  adjective
• mutationally
  adverb
• nonmutationally
  adverb

Inflected Forms

Nouns

• mutations
  plural

Etymology

Origin of mutation

First recorded in 1325–75; Middle English mutacio(u)n, from Latin mūtātion- (stem of mūtātiō ) “a changing”; see mutate, -ion

Explanation

A mutation is a genetic change that causes new and different characteristics, like the mutation on the dog's DNA that makes its tail shorter than its ancestors' tails. Mutation comes from the Latin word mutationem meaning "a changing." You might recognize this root in related words like mutate, mutable, and mutant. We often think of mutations as changes in an animal's genetic structure, but there are other kinds of mutations. For example, if an architect designs an award-winning building, her later designs that are similar might be called mutations of that one.

Example Sentences

See Examples For:

mutation mutations

Over generations, the trait propagates through the population until what was once a rare mutation becomes commonplace.

From The Wall Street Journal ● Jul. 24, 2026

The newly calculated mutation rate does more than clarify the koala's ancient past.

From Science Daily ● Jul. 17, 2026

Earlier work from Alder's laboratory had identified frequent mutations in a telomere binding protein called TPP1 while analyzing cancer mutation databases.

From Science Daily ● Jul. 1, 2026

At Strong4Life, they learned that the boys have a genetic mutation that affects the perception of fullness and increases the risk of obesity.

From The Wall Street Journal ● Jun. 22, 2026

In this light, one can examine a crop widespread in prehistoric times and ask whether all of its varieties show the same wild mutation or same transforming mutation.

From "Guns, Germs, and Steel: The Fates of Human Societies" by Jared M. Diamond

The results show that the genes a person is born with can interact with mutations acquired later in life, shaping the evolutionary path a tumor follows.

From Science Daily ● Jul. 27, 2026

Cancer begins when DNA errors, known as mutations, accumulate inside cells.

From Science Daily ● Jul. 27, 2026

Dorio said there are thousands of cancer mutations for which there are thousands of therapies, and in the modern world of medical advances and telehealth capability, no one is served by restricting access to care.

From Los Angeles Times ● Jul. 18, 2026

Through DNA sequencing, Dr. Lutter found that Gordon also had one of these mutations.

From The Wall Street Journal ● Jul. 8, 2026

We can sequence human DNA, and identify genetic mutations that cause, for example, diabetes.

From "The Invention of Science" by David Wootton

Related Words

• alteration
• anomaly
• variation