How mutation rate evolves: Gene expression shapes genome-wide mutation rates in Drosophila melanogaster and Caenorhabditis elegans

Higher transcription-coupled repair is linked to lower de novo single-nucleotide variant rates in conserved loci in Drosophila melanogaster and Caenorhabditis elegans, shaping genome-wide mutation landscapes.

• Why it matters: Mutation rates vary across genomes and correlate with functional features, but it was unclear whether gene regulation and repair mechanisms explain reduced mutation at strongly conserved genes in animals.
• What they did: The study reanalyzed published mutation accumulation datasets to relate genome-wide DNV rates to sequence and regulatory variables, then used XR-sequencing to test transcription-coupled repair associations.
• The result: Loci under stronger purifying selection accumulated fewer mutations, and higher transcription-coupled repair correlated with reduced mutation rates, supporting a model where developmental transcription modulates local mutation via TCR.

AI summary of the abstract · may contain errors · not medical advice · read the paper.