Overview

• Researchers divided the MER11 family into four evolutionary subfamilies (G1–G4) through a phylogeny-based reclassification published in Science Advances in July 2025.
• LentiMPRA assays in human stem cells confirmed that the youngest group, MER11_G4, exhibits the highest gene activation potential among the subfamilies.
• Comparative analysis across humans, chimpanzees, and macaques revealed species-specific mutations in MER11_G4 that alter transcription factor motifs and regulatory functions.
• Extending their phylogenetic approach across 18 other LTR groups, the team uncovered 75 previously unrecognized simian subfamilies influencing gene regulation landscapes.
• Findings underscore how endogenous retroviral LTRs have been repurposed as gene regulatory elements, prompting refined genome annotation and new evolutionary insights.