The hidden costs of selective breeding: What’s behind the success in sport-hunting dogs?

Genetics underpins the process of selective breeding in dogs, enabling the production of specific combinations of phenotypes. Dogs are categorized by roles; sport-hunting breeds, such as retrievers, spaniels, pointers, and setters, belong to the sporting group, bred to assist hunters over large distances.

Insight into the molecular mechanisms underpinning the creation of dog breeds was provided by an important study by Kim et al. in 2018, which identified 59 genes under strong selection in sport-hunting dogs. These genes impact cardiovascular, neuronal, and muscular functions, crucial for endurance and physical demands. Notably, the ASIC3 gene mutation in these breeds may reduce post-exercise muscle pain, offering an evolutionary advantage. Studies such as this have highlighted that behaviors like herding and hunting are shaped by genetic predispositions as much as training. However, while selective breeding achieves desired traits, it risks genetic diseases due to inbreeding. To continue to advance the creation and maintenance of dog breeds with specific traits, ethical breeding, including genetic screening and reducing inbreeding, is essential to mitigate health risks while preserving diverse, purpose-driven dog breeds. As dog owners, it is our responsibility to balance selective breeding benefits with its long-term impacts.

Creator: Chloris Jiang

References:
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