Circular extra-chromosomal dna elements

摘要

The present invention provides novel circular extra-chromosomal DNA (CED) elements isolated from a wide diversity of organisms. The CED elements range in size from about 40 kb to about 110 kb, are resistant to lambda exonuclease and contain at least one open reading frame. Such CED elements can be modified using standard molecular biological techniques tailor their use to various applications, for example, by incorporation of heterologous nucleic acid sequences. The present invention also pertains to a method of isolating the CED elements from animal tissue. The CED elements may be used in genetic testing and as a stable expression element.