Why must animal breeders use immunogenetics cautiously when selecting for disease resistance?

In the field of animal breeding, breeders must exercise caution when applying immunogenetics to select for disease resistance because immune systems have evolved to be generally robust and highly complex.1

Modifying the frequency of specific genes that regulate immune function can lead to unintended consequences, as these genes often interact with others. Altering one gene may inadvertently disrupt the function of another, resulting in adverse effects on the animal. Furthermore, the phenotypic expression of these traits is not determined by genetics alone; it is influenced by complex interactions between multiple genes and the environment, which can trigger or suppress gene activity.1

Because of these intricate dependencies, researchers must carefully consider how specific genes interact within the context of a broader breeding scheme. While immunogenetics offers potential for improving livestock health, the current ability to predict an animal's health based on immune response markers remains limited, necessitating a cautious approach to ensure that selection efforts do not compromise overall biological fitness.1