F₂ Repulsion Progeny Part II

The A_B_ class has the proportion (p² +2)/4 for repulsion linkage. Now let us find the proportion for the other three classes.

(1-p)² + p(1-p) + p(1-p) = 1 - 2p + p² + p - p² + p - p²
  4           4          4                         4

= -p² + 1 = 1 - p²
        4         4

(1-p)² + p(1-p) + p(1-p) =  1-p²
              4                        4

Finally there is only one combination that results in the aabb genotype with probability p²/4.

Example

We can sum the probability of all genotypes that are phenotypically A_B_ or A_bb or aaB_, or aabb.

r = n, s = -a₁ + 2a₂ + 2a₃ + 2a₄, t = -2a₄

r = 1415, s = -753 + 2(292) + 2(351) + 19 = 552, t = -2(19) = -38