Exploring the Italian equine gene pool via high-throughput genotyping

Area of Science:

• Animal Genetics
• Equine Genomics
• Population Genetics

Background:

• The Italian peninsula's central Mediterranean location fostered rich biodiversity, including diverse horse populations.
• Historical events, including warfare and colonization, have significantly impacted the Italian equine gene pool.

Purpose of the Study:

• To analyze the genetic status of the modern Italian equine population.
• To compare Italian breeds with influential cosmopolitan breeds and global equine diversity.

Main Methods:

• Genotyping of 1,308 individuals across 22 Italian breeds at 70k density.
• Merging with publicly available data for a total of 1,333 individuals from 54 populations.
• Analysis of multidimensional scaling, admixture, gene flow, and effective population size.

Main Results:

• Some native Italian breeds retain distinct gene pools, likely due to adaptation to diverse Italian geography.
• Significant gene flow from renowned international breeds into several Italian breeds was observed, indicating historical introgression.
• Coldblood breeds showed stronger genetic identity compared to highly admixed warmblood breeds.

Conclusions:

• Italian horse breeds exhibit varied genetic distinctiveness, influenced by adaptation and historical crossbreeding.
• Certain breeds may be maintained more for cultural and geographical reasons than for unique genetic identity.
• Understanding these genetic dynamics is crucial for effective conservation and breeding strategies.