Overview
- A University of Vienna study published Friday reconstructed three‑dimensional genomes for an octopus, a cuttlefish and a bobtail squid to test how genome shape relates to complex traits.
- The team reports an ancient burst of chromosome reshuffling brought distant DNA regions into contact and that those new contacts became embedded as interconnected regulatory networks the authors call “regulatory entanglement.”
- Comparative maps showed the California two‑spot octopus genome is especially rearranged, creating more long‑range contacts between regions that were once far apart.
- A targeted deletion of roughly 1,000 DNA letters in a bobtail‑squid relative produced developmental delays and varied morphological defects in 25 embryos while changing activity of genes millions of letters away, providing functional evidence that distant contacts can influence gene regulation.
- The authors found large chromatin domains stayed stable over evolution while finer chromatin loops were highly dynamic and often sat near nervous‑system genes, a pattern that supports a role for 3D folding in generating new traits but also calls for more work to link folding directly to behavior.