Definition of penetrance in English:

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Pronunciation: /ˈpɛnɪtr(ə)ns/


[mass noun] Genetics
The extent to which a particular gene or set of genes is expressed in the phenotypes of individuals carrying it, measured by the proportion of carriers showing the characteristic phenotype.
Example sentences
  • Because of reduced penetrance, individuals of different genotypes can have the same phenotype.
  • With the exception of the relatively rare high penetrance, single gene disorders, genetic tests differ little from most other medical tests, providing evidence of statistical risk only.
  • High penetrance susceptibility genes probably account for no more than 5-10% of cases.


1930s: from German Penetranz.

For editors and proofreaders

Line breaks: pene|trance

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