A system, device and method for receiving multiple aligned genetic sequences obtained from genetic samples of multiple organisms of one or more different species. A measure of evolutionary variation may be computed for one or more alleles at each of one or more aligned genetic loci. The aligned genetic loci in the multiple organisms may be derived from one or more common ancestral genetic loci or may be otherwise related. The measure of evolutionary variation may be a function of variation in alleles at corresponding aligned genetic loci in the multiple aligned genetic sequences. One or more likelihoods may be computed that an allele mutation at each of the one or more genetic loci in a simulated virtual progeny will be deleterious based on the measure of evolutionary variation of alleles at the corresponding aligned genetic loci for the multiple organisms.