Extrachromosomal Circular DNA are composed of chromatin and replicate in the nucleus of the cell during cell division. Unlike typical chromosomes, they are composed of circular fragments of DNA, up to only a few million base pairs in size and contain no centromere or telomere. Extrachromosomal Circular DNA Extrachromosomal circular DNA (eccDNA) is circular DNA found in the nuclei of plant and animal cells, including human cells, in addition to chromosomal DNA. eccDNA can be from 200 up to 5 million base pairs in length. eccDNA has been found in the nuclei of human cancer cells and shown to carry many copies of
Single-cell DNA template strand sequencing Single-cell DNA template strand sequencing Single-cell DNA template strand sequencing, or strand-seq, is a technique for the selective sequencing of a daughter cell’s parental template strands. This technique has many applications, including the identification of sister chromatid exchanges in the parental cell prior to segregation, the identification of misoriented contigs during alignment of reads to the reference genome, and the assessment of non-random segregation of sister chromatids. Strand-seq (single strand sequencing) was first described in 2012 as a technique to isolate sequenced reads from parental template strands in single-cell DNA libraries. As a proof of concept study, the authors demonstrated