Lepidopteran Genomes Have Denser Transposable Elements in Smaller Chromosomes, Likely Driven by Non-allelic Homologous Recombination.

ABSTRACT: Transposable elements (TEs) drive major genome size and structural variations, yet evolutionary forces affecting their accumulation and removal remain unclear. Classical models predict that higher recombination rates lead to more efficient purifying selection, such as TE removal. However, in the painted lady butterfly (Vanessa cardui), smaller chromosomes harbor denser TE content than larger ones despite higher recombination rates. This unexpected pattern raises questions about whether similar trends occur across other Lepidoptera species and what evolutionary forces are behind this pattern. Across ten species spanning ten lepidopteran families, we investigated the relationship between chromosome size and TE organization using comparative genomics. We observed that smaller chromosomes cons

SUBMITTER: An H 

PROVIDER: S-EPMC12308830 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature