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 team bases its conclusion on the fact that Laron syndrome is caused by a mutation in the growth hormone receptor in the liver.

From BBC ● Jul. 17, 2026

Those estimates, however, were based on mutation rates taken from distantly related mammals such as humans and mice.

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

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

From "Middlesex: A Novel" by Jeffrey Eugenides

Inherited genetic differences can also influence how many mutations build up and how cells respond to them.

From Science Daily ● Jul. 27, 2026

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

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

Plants treated with various phenols suffered profound destruction of chromosomes, changes in genes, a striking number of mutations, “irreversible hereditary changes.”

From "Silent Spring" by Rachel Carson

Related Words

• alteration
• anomaly
• variation