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

These occur when an individual gains a beneficial mutation that gives it an advantage over closely related individuals, allowing its descendants to become dominant.

From Science Daily ● Sep. 7, 2026

The FDA approved Revolution Medicines’ drug Rasonque, a milestone therapy that targets a mutation in pancreatic cancer.

From The Wall Street Journal ● Aug. 26, 2026

Those mutation targets are encoded into mRNA and manufactured into a vaccine—a process that takes about six weeks from the date of the biopsy.

From The Wall Street Journal ● Aug. 19, 2026

"This could help explain why people with the same mutation can have different heart defects," Grant says.

From Science Daily ● Aug. 13, 2026

My grandparents, unaware of their genetic mutation, concentrated on die more blatant disqualifications.

From "Middlesex: A Novel" by Jeffrey Eugenides

Such regions may become especially significant when mutations interfere with normal cellular activity and contribute to cancer.

From Science Daily ● Sep. 10, 2026

It looks for more than 450 DNA mutations associated with bladder cancer across 23 genes.

From BBC ● Sep. 2, 2026

Among North Eurasian populations, chitinase genes contain mutations associated with a reduced ability to digest insect exoskeletons.

From Science Daily ● Aug. 27, 2026

The vaccine analyzes a patient’s tumor, selects up to 34 mutations as targets and trains the immune system to recognize them.

From The Wall Street Journal ● Aug. 23, 2026

Significant changes in social behaviour cannot occur, in general, without genetic mutations.

From "Sapiens: A Brief History of Humankind" by Yuval Noah Harari

Related Words

• alteration
• anomaly
• variation