. Author manuscript; available in PMC: 2023 Jun 7.

Published in final edited form as: Nat Struct Mol Biol. 2022 Aug 10;29(8):736–744. doi: 10.1038/s41594-022-00806-7

Table 1.

Differences between ecDNA and eccDNA.

ecDNA	eccDNA
100 kb to several megabases	Several hundred to thousand bases^19,22
Circular	Circular
Self-replicating	Not known to replicate
Clonally selected	Typically not amplified or selected
Contains oncogenes, drug resistance genes, or other genes that provide a selective advantage^{3–13,28,101}	Sequences cover the entire genome with some hotspots; typically does not contain genic sequences¹⁹
Contains regulatory sequences such as oncogene enhancers^24,46,48,53	Usually does not contain regulatory sequences
Found in cancer cells	Found in many cell lines and tissues, including healthy samples^{20,22,102–104}
Can contain heavily recombined genomic sequences and specific mutations^49,87	Not known to carry mutations