Impact of Repetitive DNA Elements on Snake Genome Biology and Evolution

The distinctive biology and unique evolutionary features of snakes make them fascinating model systems to elucidate how genomes evolve and how variation at the genomic level is interlinked with phenotypic-level evolution. Similar to other eukaryotic genomes, large proportions of snake genomes contain repetitive DNA, including transposable elements (TEs) and satellite repeats. The importance of repetitive DNA and its structural and functional role in the snake genome, remain unclear. This review highlights the major types of repeats and their proportions in snake genomes, reflecting the high diversity and composition of snake repeats. We present snakes as an emerging and important model system for the study of repetitive DNA under the impact of sex and microchromosome evolution. We assemble evidence to show that certain repetitive elements in snakes are transcriptionally active and demonstrate highly dynamic lineage-specific patterns as repeat sequences. We hypothesize that particular TEs can trigger different genomic mechanisms that might contribute to driving adaptive evolution in snakes. Finally, we review emerging approaches that may be used to study the expression of repetitive elements in complex genomes, such as snakes. The specific aspects presented here will stimulate further discussion on the role of genomic repeats in shaping snake evolution.

Automated summary

Snakes have unique biological features and evolutionary characteristics, making them fascinating model systems for studying genomic evolution and the relationship between variation at the genomic level and phenotypic-level evolution. Snake genomes, similar to other eukaryotic genomes, are composed of a large proportion of repetitive DNA, including transposable elements and satellite repeats. The significance of repetitive DNA in snake genomes, particularly its structural and functional roles, remains unclear. The study highlights the diversity and composition of repetitive DNA in snake genomes, presenting snakes as an emerging and important model system for understanding the impact of repetitive DNA under sex and microchromosome evolution. Certain repetitive elements in snakes are found to be transcriptionally active and show highly dynamic lineage-specific patterns as repeat sequences, suggesting that they may trigger genomic mechanisms contributing to adaptive evolution in snakes. New approaches are reviewed for studying the expression of repetitive elements in complex genomes, such as snakes, to further explore the role of genomic repeats in shaping snake evolution.