Previously formulae have been given for both joint and conditional match probabilities for some relationships that did not account for subpopulation effects [1,2]. In this paper the researchers extend these works to include a subpopulation correction of the form first suggested by Balding and Nichols [3].
Often the loci in forensic multiplexes are selected to avoid linked loci. However linked loci have occurred in some recent commercially available multiplexes. Previously formulae have been given for both joint and conditional match probabilities for some relationships that did not account for subpopulation effects [1,2]. In this paper the researchers extend these works to include a subpopulation correction of the form first suggested by Balding and Nichols [3]. The researchers extend the work to grandparent/grandchild, first cousin, uncle/nephew and half uncle/nephew relationships and apply these to two different populations and STR multiplexes. The model assumes that the two people have no relationship other that the one specified. That is, the researchers assume their parents are neither related nor themselves inbred. The multiplications inherent in these formulae also assume that there is no linkage disequilibrium at the subpopulation level for these loci. The researchers found that when taking into account linkage the match statistic decreases for all relationships, with siblings having the greatest effect. However, the effect was less than a factor of two decreased in match statistic. (Published Abstract)