kataegis
Pronunciation: kat-ah-EE-gis
A localized hypermutation phenomenon characterized by clusters of C-to-T and C-to-G mutations occurring in close proximity on the same chromosome strand.
Full Definition
Kataegis refers to regions of localized hypermutation where cytosine-to-thymine (C-to-T) and cytosine-to-guanine (C-to-G) substitutions cluster together, typically within a few kilobases. These mutation clusters often occur near sites of chromosomal rearrangements and are associated with APOBEC enzyme activity. In cancer genomics, kataegis patterns are visualized as 'rainfall plots' showing mutation density along chromosomes. The term derives from the Greek word meaning 'thunderstorm,' reflecting the intense, localized nature of the mutagenic process. Recognition of kataegis is important for understanding tumor mutagenesis mechanisms and interpreting mutation burden.
Usage
Usage note: Often presented with rainfall plots; distinguish from general hypermutation.
In Context
- "Kataegis was evident in the rainfall plot, with C-to-T mutation clusters near the chromosomal breakpoints." — Genomic analysis report
- "The APOBEC-associated kataegis pattern suggested ongoing DNA damage in this tumor type." — Research manuscript