Heritability is particularly relevant and useful, especially when it comes to traits for which there are no specific genetic tests yet. This measure indicates the proportion of observed variation in a particular trait that can be attributed to genetic differences within a population. In cases where specific genetic markers or tests for certain traits are lacking, heritability can still provide valuable insights into the genetic contribution to these characteristics.
For breeders and geneticists, knowledge of heritability offers the opportunity to develop targeted breeding programs, even for traits where the exact genetic foundations are not fully understood. When the heritability of a trait is high, it suggests that genetic factors have a strong influence on the variation in that trait. In such cases, breeders can selectively choose dogs that exhibit the desired trait to increase the likelihood of its enhancement in subsequent generations.
These heritability-based approaches allow for genetic progress and improvement of traits, even when the underlying genetic mechanisms are not fully known. However, it is essential to emphasize that heritability should not be the sole basis for breeding decisions. Environmental factors and complex genetic interactions also play a role and should be considered in the development of breeding strategies.
Example
Let’s consider the susceptibility of dogs to allergies, particularly to specific food allergies. If research indicates that the predisposition to food allergies in dogs has a certain heritability, it would suggest that genetic factors significantly influence the variation in this allergic behavior.
In breeding practices, breeders could aim to influence the predisposition to food allergies in their lines. If heritability is high, they might select dogs that are less susceptible to food allergies, hoping to decrease the likelihood of these allergic reactions in subsequent generations.
However, it’s important to note that allergies involve a complex interplay of genetic and environmental factors. The environment in which a dog grows up, its diet, and other environmental conditions play a substantial role in the development of allergies. Heritability simply indicates the portion of variability in susceptibility to food allergies attributable to genetic differences.
Breeders should consider not only genetic predisposition but also environmental factors that can influence the development of allergies. A comprehensive approach that takes into account both genetic and environmental aspects is crucial to minimize the occurrence of allergies in dog populations.
