On the other hand, the dependency of HDR on a homologous sequence to repair DSBs can be exploited by inserting a desired sequence within a sequence that is homologous to the flanking sequences of a DSB which, when used as a template by HDR system, would lead to the creation of the desired change within the genomic region of interest.
32.
Homologous sequences are "'orthologous "'if they are inferred to be descended from the same ancestral sequence separated by a speciation event : when a species diverges into two separate species, the copies of a single gene in the two resulting species are said to be orthologous . "'Orthologs "', or orthologous genes, are genes in different species that originated by vertical descent from a single gene of the last common ancestor.
33.
Like other members of the Rad51 / RecA family, Dmc1 stabilizes strand exchange intermediates ( Rad1 / RecA-stretched DNA, or RS-DNA ) in stretched triplets similar to B form DNA . Each molecule of the protein binds a triplet of nucleotides, and the strength of that binding, as assessed by the change in Gibbs free energy, can be assessed by the length of time that a labelled dsDNA probe with a short homologous sequence remains bound to a DNA containing a short region of homology to it.
