 “Additive genetic variation \((V_{A})\) is variation among individuals due to the additive effects of genes” (Freeman and Heron, 206). For example, variation in height of organisms could result from the contribution of several alleles at a locus where each allele contributes more height to the organism. More precisely, allele A could contribute .5 units to an organism’s height, allele a another .5 units and so on. A contrast with additive genetic variance is dominance variance \((V_{D})\). In this case, say two alleles (A and a) are responsible for the organism’s height. An organism with aa is 1.0 units high, an organism with AA is 2.0 units high but an organism with Aa is also 2.0 units high. Total genetic variance, \(V_G\), is actually the sum of all the genetic variance. In the simplified case presented here this is