• The Pax gene family is evolutionarily conserved across vertebrates, with Lr.Pax7 in lamprey showing high sequence similarity to higher vertebrates, supporting lamprey as a model for studying gene evolution.
• Lr.Pax7 is most closely related to Petromyzon marinus Pax7, positioning lamprey between vertebrates and invertebrates and providing insights into the ancestral state of Pax genes.
• Structural predictions indicate that Lr.Pax7 shares a highly homologous pair-box domain with human Pax7, suggesting conserved DNA-binding and regulatory functions.
• This study establishes a foundation for functional exploration of Pax7 in lamprey, potentially revealing ancestral roles in muscle and neural development.