Pedigrees and arrow diagrams provide useful visual aids for relationships among animal species and cross fertilizing plants. The diagram illustrates the concept of a parent-progeny mating. In some cases this type of mating may occur intentionally, and in some cases it may occur accidentally.
The degree of inbreeding based on pedigree information is referred to as an inbreeding coefficient. Consider the following principles:
i. The inbreeding coefficient for any individual is calculated as half of the additive genetic covariance of the individual’s parents.
ii. The additive genetic covariance for any pair of individuals is the sum of the relationship paths that connect those two individuals.
Based on the diagram and the two principles above, the inbreeding coefficient of an individual resulting from a parent-progeny mating is