Genet. Sel. Evol. 35 (2003) 369-383
DOI: 10.1051/gse:2003029

Pedigree and marker information requirements to monitor genetic variability

Roswitha Baumung and Johann Sölkner

Department of Livestock Sciences, University of Agricultural Sciences, Gregor Mendel-Str. 33, 1180 Vienna, Austria
(Received 22 April 2002; accepted 15 January 2003)

Abstract
There are several measures available to describe the genetic variability of populations. The average inbreeding coefficient of a population based on pedigree information is a frequently chosen option. Due to the developments in molecular genetics it is also possible to calculate inbreeding coefficients based on genetic marker information. A simulation study was carried out involving ten sires and 50 dams. The animals were mated over a period of 20 discrete generations. The population size was kept constant. Different situations with regard to the level of polymorphism and initial allele frequencies and mating scheme (random mating, avoidance of full sib mating, avoidance of full sib and half sib mating) were considered. Pedigree inbreeding coefficients of the last generation using full pedigree or 10, 5 and 2 generations of the pedigree were calculated. Marker inbreeding coefficients based on different sets of microsatellite loci were also investigated. Under random mating, pedigree-inbreeding coefficients are clearly more closely related to true autozygosity (i.e., the actual proportion of loci with alleles identical by descent) than marker-inbreeding coefficients. If mating is not random, the demands on the quality and quantity of pedigree records increase. Greater attention must be paid to the correct parentage of the animals.

Key words: autozygosity / inbreeding / microsatellite / quality of pedigree

Correspondence and reprints: Roswitha Baumung
    e-mail: baumung@boku.ac.at

© INRA, EDP Sciences 2003