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
Cell-free fetal DNA with single base specificity and single DNA molecule sensitivity. DNA is amplified by PCR. Then, linear amplification with base extension reaction (with a third primer) is designed to anneal to the region upstream from the mutation site. One or two bases are added to the extension primer to produce two extension products from wild-type DNA and mutant DNA. Single base specificity provides advantages over hybridization-based techniques using TaqMan hydrolysis probes. When assessing the technique, no false positives or negatives were found when looking for cffDNA to determine fetal sex in sixteen maternal plasma samples. The sex of ninety of ninety-one