Genomic Variation and Population Structure of Portuguese Native Dog Breeds

Area of Science:

• Canine genomics
• Population genetics
• Evolutionary biology

Background:

• Zooarchaeological evidence confirms dogs in Portugal for at least 7600 years.
• Portugal harbors 11 native dog breeds, products of a complex evolutionary history.

Purpose of the Study:

• Characterize genomic diversity and population structure of 10 Portuguese native dog breeds.
• Conduct a worldwide population genomics analysis using whole-genome sequencing (WGS) and SNP data.
• Identify breed-specific evolutionary events and genetic signatures.

Main Methods:

• Whole-genome sequencing (WGS) of 46 dogs from 10 native Portuguese breeds.
• Integration with public genome data and downsampling to Illumina Canine HDBeadChip data.
• Analysis of 1770 dogs from 211 breeds for global population genomics.

Main Results:

• High autosomal diversity and low to moderate inbreeding observed across breeds.
• Identification of multiple maternal haplotypes across haplogroups A-D.
• Breed-specific genomic signatures reveal diverse histories including isolation, admixture, shared ancestry, and bottlenecks (e.g., Portuguese Water Dog).

Conclusions:

• Portuguese dog breeds exhibit shallow genetic differentiation with varying degrees of homogeneity and substructure.
• Genomic insights underscore the importance of preserving these breeds for their contribution to canine genomic diversity.
• Findings provide a basis for conservation and genetic management strategies for locally adapted dog breeds.