Jumping Genes (Transposable Elements): A Comprehensive Review of Their Molecular Mechanisms, Evolutionary Impact and Applications in Livestock and Biomedicine

Abstract

Transposable elements (TEs), commonly referred to as “jumping genes,” are discrete DNA fragments capable of mobilization within the genome, often creating new copies during transposition. Once considered non-functional “junk DNA,” TEs are now recognized as essential regulators of genome evolution, gene networks, and epigenetic processes. They contribute to genome innovation through gene duplication, exon shuffling, regulatory rewiring, and stress-responsive plasticity. Conversely, their uncontrolled activation can disrupt genetic integrity. Such aberrant TE activity has been associated with immune dysfunction, cancer, neurodegeneration, and reproductive disorders. In livestock, recent studies have identified TE-derived regulatory elements that influence growth, reproduction, immunity, and adaptation. Notably, TEs constitute approximately 45–60% of the genomes of major livestock species, including pigs, sheep, and cattle, highlighting their extensive regulatory impact. Advances in genome editing and artificial intelligence have facilitated their functional characterization. This allows a sharper focus on TE-driven regulation in animal genomes without repeatedly specifying the livestock context. Emerging technologies such as CRISPR–transposon systems, programmable epigenome editing, and AI-driven TE mapping offer new opportunities for precise genome engineering, functional genomics, and livestock breeding. This review consolidates current knowledge on TE classification, molecular mechanisms, evolutionary roles, disease associations, and biotechnological  applications, with emphasis on livestock genomics. It also outlines existing challenges, biosafety considerations, and future directions toward harnessing TEs for precision animal breeding and synthetic biology.