Extrachromosomal DNA DNA in a variety of different organisms. Extrachromosomal DNA Extrachromosomal DNA is any DNA that is found outside the nucleus of a cell. It is also referred to as extranuclear DNA or cytoplasmic DNA. Most DNA in an individual genome is found in chromosomes but DNA found outside the nucleus also serves important biological functions. In prokaryotes, nonviral extrachromosomal DNA is primarily found in plasmids whereas in eukaryotes extrachromosomal DNA is primarily found in organelles. Mitochondrial DNA is a main source of this extrachromosomal DNA in eukaryotes. The fact that this organelle contains its own DNA supports the hypothesis that
Single-cell DNA template strand sequencing the ability to acquire sequence information from the Watson and/or Crick chromosomal strands in an individual DNA library, depending on the mode of chromatid segregation; a typical DNA library will always contain DNA from both strands. The authors were specifically interested in showing the utility of strand-seq in detecting sister chromatid exchanges (SCEs) at high-resolution. They successfully identified eight putative SCEs in the murine (mouse) embryonic stem (meS) cell line with resolution up to 23 bp. This methodology has also been shown to hold great utility in discerning patterns of non-random chromatid segregation, especially in stem cell lineages. Furthermore, SCEs