The construction of a combined physical-genetic map for a breed of dairy cattle in Germany

Contact: Dr. Dörte Wittenburg

Duration: 2019-2022

Funding: Bundesministerium für Bildung und Forschung

In animal breeding, genomic markers are used to characterise genetic variation in a population. The distance between markers can be measured on two scales: physical and genetic. The latter is more of interest to the breeder because it is related to the probability that variants at two markers are transmitted jointly from parent to offspring. This probability is determined by the so-called recombination rate. Our approach will bring together physical and genetic measures of the proximity of molecular markers for the main national dairy breed to produce a combined physical-genetic map. We will develop software tools that take into account family structures in cattle to estimate recombination rates and other population genetic parameters. The relationship between recombination rate and physical position on the genome will be elucidated by an improved statistical model that takes into account local phenomena of recombination activity. Using the genetic mapping function that fits best to the bovine genome, the genetic distance will be determined. We expect that the results of our study will have a major impact on the design of breeding strategies and will increase the genetic and economic efficiency of dairy cattle breeding. The developed tools are tailored to population genetic questions. Our analytical approach and calculation pipeline can help scientists in related research fields to create genetic maps for other species. The planned Open Access database will be open for extensions to other cattle breeds and allows comparison with other species.