[ pen-i-truh ns ]
/ ˈpɛn ɪ trəns /

noun Genetics.

the frequency, expressed as a percentage, with which a particular gene produces its effect in a group of organisms.Compare expressivity(def 2).

Origin of penetrance

First recorded in 1635–45; penetr(ant) + -ance Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Examples from the Web for penetrance

British Dictionary definitions for penetrance

/ (ˈpɛnɪtrəns) /


genetics the percentage frequency with which a gene exhibits its effect

Word Origin for penetrance

C20: from penetr (ant) + -ance, on the model of German penetranz
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Medical definitions for penetrance

[ pĕnĭ-trəns ]


The frequency, under given environmental conditions, with which a specific genotype is expressed by those individuals that possess it, usually given as a percentage.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.