copy number variant
Chromosomal segment that varies in copy number between individuals. May be pathogenic, benign, or of uncertain significance.
Full Definition
A type of structural genetic variation involving deletions or duplications of DNA segments that are typically 1 kilobase or larger, resulting in individuals having different numbers of copies of particular genomic regions. Copy number variants represent a normal part of human genetic diversity, with each individual carrying dozens to hundreds of CNVs throughout their genome. However, some CNVs can be pathogenic when they disrupt important genes or regulatory elements, while others may predispose to disease or influence drug responses. The clinical significance of a CNV depends on its size, gene content, inheritance pattern, and comparison with population databases.
Usage
Usage note: Specify size and chromosomal location when discussing specific CNVs in clinical contexts.
In Context
- "The 600 kb copy number variant on chromosome 16p11.2 was classified as likely pathogenic for neurodevelopmental disorders." — Genetic testing interpretation
- "Population studies reveal that copy number variants contribute significantly to normal human genetic diversity." — Research publication