Genome-Wide Association Study for Body Length, Body Height, and Total Teat Number in Large White Pigs

Area of Science:

• Animal Genetics
• Quantitative Genetics
• Genomic Selection

Background:

• Body length, height, and total teat number are crucial economic traits in pig breeding, impacting growth, reproduction, and longevity.
• Understanding the genetic basis of these traits is essential for effective breeding programs.

Purpose of the Study:

• To conduct a genetic analysis of body length, body height, and total teat number in a Large White pig population.
• To estimate heritability and genetic correlations for these traits.
• To identify candidate genes and genomic regions associated with these economically important traits.

Main Methods:

• Genotyping-by-sequencing (GBS) for high-density SNP discovery and genotyping in 2,068 Large White pigs.
• Univariate and bivariate animal models to estimate heritability and genetic correlations.
• Genome-wide association study (GWAS) using single-locus and weighted single-step (WssGWAS) approaches.

Main Results:

• Heritability estimates: body length (0.25 ± 0.04), body height (0.11 ± 0.03), and total teat number (0.22 ± 0.04).
• Strong positive genetic correlation between body length and height (0.63 ± 0.15).
• Significant SNPs identified, including one near BMP2 associated with body length and height, and another in ABCD4 associated with teat number.

Conclusions:

• The genetic architecture of body length, height, and teat number is complex.
• Identified candidate genes and genomic regions provide a foundation for future genetic research.
• Findings support the application of genomic selection for improving these traits in pig breeding.