Table 2 Partition of degrees of freedom for two loci with number of alleles n₁ and n₂ (a simplified case without distinguishing the paternal and maternal origins)

additive (α)

n₁ - 1

dominance (δ)

n₁(n₁ - 1)/2

additive (β)

n₂ - 1

dominance (γ)

n₂(n₂ - 1)/2

additive × additive (αβ)

(n₁ - 1)(n₂ - 1)

additive × dominance (αγ)

(n₁ - 1)n₂(n₂ - 1)/2

dominance × additive (δβ)

n₁(n₁ - 1)(n₂ - 1)/2

dominance × dominance (δγ)

n₁(n₁ - 1)n₂(n₂ - l)/4

total

$\frac{n_1(n_1+1)}{2}\cdot \frac{n_2(n_2+1)}{2}-1$