T2T genomes of Caenorhabditis nigoni and Caenorhabditis briggsae reveal divergence in satellite DNA abundance.
Long-read sequencing reveals that Caenorhabditis nigoni has 4.0 times more satellite DNA than C. briggsae, significantly contributing to genome size differences.
- Why it matters: Understanding genome divergence in closely related species helps clarify the role of repetitive DNA in genome evolution and reproductive strategies, addressing gaps in previous genic-focused analyses.
- What they did: Researchers generated complete telomere-to-telomere genomes for both species, resolving gaps and scaffolds, and quantified satellite DNA and rDNA variations using long-read sequencing.
- The result: The findings highlight satellite DNA as a major factor in genome size divergence and reveal structural differences in the X chromosome, providing insights into repetitive DNA evolution.