Marker-based estimates of between and within population kinships for the conservation of genetic diversity

In this article coefficients of kinship between and within populations are proposed as a tool to assess genetic diversity for conservation of genetic variation. However, pedigree-based kinships are often not available, especially between populations. A method of estimation of kinship from genetic marker data was applied to simulated data from random breeding populations in order to study the suitability of this method for livestock conservation plans. Average coefficients of kinship between populations can be estimated with low Mean Square Error of Prediction, although a bias will occur from alleles that are alike in state in the founder population. The bias is similar for all populations, so the ranking of populations will not be affected. Possible ways of diminishing this bias are discussed. The estimation of kinships between individuals is imprecise unless the number of marker loci is large (> 200). However, it allows distinction between highly related animals (full sibs, half sibs and equivalent relations) and animals that are nor directly related if about 30-50 polymorphic marker genes are used. The marker-based estimates of kinship coefficients yielded higher correlations than genetic distance measures with pedigree-based kinships and thus to tills measure of generic diversity, although correlations were high overall. The relation between coefficients of kinship and generic distances are discussed. Kinship-based diversity measures conserve the founder population allele frequencies, whereas generic distances will conserve populations in which allele frequencies are che most different. Marker-based kinship estimates can be used for the selection Of breeds and individuals as contributors to a genetic a conservation programme.