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Published on: September 22, 2020
Evolutionary study of a potential selection target region in the pig
A Ojeda1, S E Ramos-Onsins, D Marletta
1Facultat de Veterinària, Departament de Ciència Animal i dels Aliments, Universitat Autònoma de Barcelona, Bellaterra, Spain.
Heredity
|May 27, 2010
Summary
Genomic variability in pigs is complex due to domestication and breeding. European pig populations show lower genetic diversity than Asian ones, influenced by Asian germplasm introgression.
Area of Science:
- Animal genomics
- Evolutionary biology
- Quantitative genetics
Background:
- Domestication and artificial selection significantly alter domestic animal genomic variability.
- The FAT1 quantitative trait locus (QTL) on porcine chromosome 4 is historically significant but its molecular basis remains unknown.
- Understanding genetic diversity is crucial for livestock breeding and conservation.
Purpose of the Study:
- To characterize nucleotide variability in a 2 Mb region surrounding the FAT1 QTL on porcine chromosome 4.
- To investigate the evolutionary history and demographic patterns of Asian and European pig populations in this region.
- To identify potential signals of selection and understand factors influencing genetic diversity.
Main Methods:
- Sequencing of 13 fragments across a 2 Mb region in 32 diverse pigs (Asian and European breeds).
- Analysis of genetic variability patterns across different loci and populations.
- Application of approximate Bayesian computation to infer demographic history and effective population size.
Main Results:
- Complex patterns of genetic variability were observed, with no clear signal of a selective sweep in any breed.
- The FABP4 fragment within the studied region exhibited significantly higher diversity.
- European pig populations possess a much lower effective population size (hundreds) compared to Asian populations (hundreds of thousands).
- A substantial portion of European genetic variability in this region is attributed to introgression from Asian germplasm.
Conclusions:
- Genetic diversity in pigs is shaped by intricate demographic processes, including bottlenecks, selection, and migration.
- Introgression from Asian to European pig populations significantly contributes to extant European genetic variability.
- Identifying selection footprints is challenging due to the confounding effects of migration and complex demographic histories.
- Further research is needed to assess the genome-wide applicability of these findings.
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