mutation

noun

mu·​ta·​tion myü-ˈtā-shən 

1

: a significant and basic alteration : change

2

: umlaut

3

a

: a relatively permanent change in hereditary material that involves either a change in chromosome structure or number (as in translocation, deletion, duplication, or polyploidy) or a change in the nucleotide sequence of a gene's codons (as in frameshift or missense errors) and that occurs either in germ cells or in somatic cells but with only those in germ cells being capable of perpetuation by sexual reproduction

Mutations known to cause disease have been identified in approximately 1000 genes.

—Alan E. Guttmacher and Francis S. Collins

also : the process of producing a mutation

Microorganisms have been used extensively to study mutation …

—George A. Wistreich et al.

b

: an individual, strain, or trait resulting from mutation

The worst E. coli bacterium, E. coli 0157:H, a mutation discovered in 1982 that has at least sixty-two subtypes, causes hemorrhagic colitis …

—Wayne Biddle

mutational

myü-ˈtā-sh(ə-)nəl 

adjective

mutationally adverb

Examples of mutation in a Sentence

The cat's short tail is the result of mutation.

The condition is caused by a genetic mutation.

The building is a mutation of the original design.

Recent Examples on the Web

Cystic fibrosis is caused by mutations in a gene known as the cystic fibrosis transmembrane conductance regulator (CFTR), says Basavaraj. —Daryl Austin, USA TODAY, 10 Feb. 2025

Researchers have found that a translocation mutation (when part of a chromosome attaches to a different one) may cause the oncogenes to multiply too quickly and lead to cancer.2 Is Multiple Myeloma Hereditary? Multiple myeloma may be partly hereditary. —Carrie Madormo, Rn, Health, 17 Jan. 2025

To monitor this risk, all H5N1-positive samples are sent to the USDA for genetic sequencing to identify mutations that may increase the virus’s ability to infect mammals and to provide important information about how the virus spreads within and between populations. —Kimberly Dodd, The Conversation, 16 Jan. 2025

If both parents carry a particular mutation, doctors will likely suggest IVF and embryo screening. —Kristen V. Brown, The Atlantic, 15 Jan. 2025

Word History

First Known Use

14th century, in the meaning defined at sense 1

Phrases Containing mutation

• back mutation
• gene mutation
• genetic mutation
• point mutation

Kids Definition

mutation

noun

mu·​ta·​tion myü-ˈtā-shən 

1

: a basic and important change

2

a

: a permanent change in hereditary material involving either a change in the position of the genes on the chromosomes or a basic change in the chemical structure of a gene

also : the process of producing a mutation

b

: an individual, strain, or trait resulting from mutation

Medical Definition

mutation

noun

mu·​ta·​tion myü-ˈtā-shən 

1

: a relatively permanent change in hereditary material that involves either a change in chromosome structure or number (as in translocation, deletion, duplication, or polyploidy) or a change in the nucleotide sequence of a gene's codons (as in frameshift or missense errors) and occurs either in germ cells or in somatic cells but with only those in germ cells being capable of perpetuation by sexual reproduction

also : the process of producing a mutation

2

: an individual, strain, or trait resulting from mutation

mutational

-shnəl, -shən-ᵊl 

adjective

mutationally

-ē 

adverb