mutation

American  

[myoo-tay-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

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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

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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

In her mid-20s, Courtney-Grace was diagnosed with a genetic mutation, which can be inherited and is associated with an increased risk of tumours.

From BBC ● Oct. 10, 2026

Pity Strong couldn’t play the CEO after his bro-y 2024 mutation into MMA-fighting Marky Mark.

From Los Angeles Times ● Oct. 9, 2026

This year’s flu season may be worsened by a mutation in the H3N2 strain, particularly in people younger than 25, according to Gounder.

From MarketWatch ● Oct. 9, 2026

More than 50 percent of the tumors examined carried a mutation in this gene.

From Science Daily ● Sep. 27, 2026

If a mutation inactivated even one function, the mold would be unable to grow—unless the missing ingredient was supplied back into the broth.

From "The Gene" by Siddhartha Mukherjee

Tumors carry mutations that can produce abnormal proteins the immune system can recognize.

From The Wall Street Journal ● Oct. 24, 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

Groups that are less likely to be lactose intolerant include northern Europeans—populations believed to have developed genetic mutations from a history of dairy herding.

From The Wall Street Journal ● Oct. 12, 2026

Researchers examined tumor samples from almost 500 domestic cats in five countries, searching for mutations and other genetic changes that help cancers form and grow.

From Science Daily ● Sep. 27, 2026

Although discussions of mutations usually refer to those in the germ cells, which may then make their effect felt in future generations, there may also be mutations in the body cells.

From "Silent Spring" by Rachel Carson

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Related Words

• alteration
• anomaly
• variation

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