de novo mutation
Pronunciation: day NOH-voh
New genetic variant that arises spontaneously and is not inherited from either parent. Often associated with advanced paternal age.
Full Definition
A genetic change that occurs spontaneously in a reproductive cell (sperm or egg) or during early embryonic development and is therefore not present in either parent's genome. De novo mutations represent new genetic variants that arise due to errors in DNA replication, repair, or recombination. These mutations are significant contributors to sporadic cases of genetic disorders, particularly in conditions affecting neurological development such as autism spectrum disorders and intellectual disabilities. The rate of de novo mutations increases with advancing paternal age, with men over 40 having approximately twice the mutation rate of men under 30.
Usage
Usage note: Use italics for the Latin phrase in formal scientific writing.
In Context
- "Trio analysis confirmed that the pathogenic MECP2 variant arose as a de novo mutation in the proband." — Genetic testing report
- "The identification of a de novo mutation provided an explanation for the isolated case in this family." — Genetic counseling documentation