Editing Inbreeding (section)

===Laboratory animals===
Systematic inbreeding and maintenance of inbred strains of [[laboratory mice]] and rats is of great importance for biomedical research. The inbreeding guarantees a consistent and uniform [[animal model]] for experimental purposes and enables genetic studies in [[congenic]] and knock-out animals. In order to achieve a mouse strain that is considered inbred, a minimum of 20 sequential generations of sibling matings must occur. With each successive generation of breeding, homozygosity in the entire genome increases, eliminating heterozygous loci. With 20 generations of sibling matings, homozygosity is occurring at roughly 98.7% of all loci in the genome, allowing for these offspring to serve as animal models for genetic studies.<ref>Taft, Robert et al. "Know thy mouse." Science Direct. Vol. 22, No. 12, Dec. 2006, pp. 649-653. Trends in Genetics. {{doi|10.1016/j.tig.2006.09.010}}</ref> The use of inbred strains is also important for genetic studies in animal models, for example to distinguish genetic from environmental effects. The mice that are inbred typically show considerably lower survival rates.