Estimation by ANOVA

When have to compute genetic and pehotypic variance for computing h2.

As it was discussed in previous parts, VP = VG + VE. Heritability is the ratio genetic (VG) and

pehotypic (VP) variance

h2 = VG /(VG +VE)

Performances of paternal half-sib groups are very often used for estimation. In this case the

phenotypic variance between, or among progeny groups is considered as genetic variance (VG,

or σ2g), while the phenotypic variance within progeny groups is considered as environmental

variance (VE, or σ2E).

The sum of these gives phenotypic variance (VP = VG + VE, vagy σ2P = σ2G + σ2E).

then

h2 = 4VG/VP = 4VG/(VG + VK,)

vagy

h2 = 4σ2g/σ2p = 4σ2g/σ2g + σ2k

The Importance of Heritability:

Heritability is a measure of genetic variation in a trait

Heritability is important for:

• Understanding the influence of genes and environment on traits
• Understanding the rate of evolution of traits
• Understanding the potential for selective breeding of traits