> “It should be noted that ecDNA is a feature of cancer and not healthy tissue, so that raises hopes that when we find ways to remove it – through drugs or some form of therapy – then it will not have unpleasant side-effects"
Hopefully it's different enough from that other DNA that doesn't occur in chromosomes: mitochondrial DNA. Also, maybe someone can explain, but hasn't there been research showing that some forms of extrachromosomal DNA are normal and probably vital in eukaryotes? E.g. [1]