Retrotransposons exploit DNA-repair pathway for circular DNA replication

Retrotransposons, a type of transposable element, have been found to hijack a DNA repair pathway called alternative end joining (alt-EJ) to facilitate their own replication and the formation of extrachromosomal circular DNA (eccDNA). Researchers discovered that alt-EJ, which is normally involved in repairing DNA double-strand breaks, is co-opted by retrotransposons to generate the necessary DNA intermediates for their replication. This study sheds light on the mechanisms underlying retrotransposon propagation and eccDNA formation, providing insights into genomic stability and potential implications for diseases such as cancer.