Genomic circular DNA can behave to transpose another-locus-derived insert accompanied by autonomous rolling circle amplification

Abstract

Abstract Extrachromosomal circular DNA from a genomic sequence was amplified by nested inverse polymerase chain reaction (PCR) using mouse and human culture cells to explore the possibility of site-specific DNA recombination. In this analysis, multiple examples of circular DNA were found to share an identical joining point. This indicates that there is a genomic site preferential for DNA recombination accompanying circular DNA production. In addition, circular DNAs with different ladder-like sizes sharing a joining point were found, which suggests the existence of endogenous rolling circle amplification. Multiple circular DNAs in which genomic fragments derived from different chromosomes were inserted were confirmed. Genome deletion was confirmed in the circular DNA formation region. These facts indicate that extrachromosomal circular DNA contributes to translocations and duplication of genomic regions that exchange genomic fragments between chromosomes in somatic cells to a greater extent than previously thought.