Mapping of porcine genetic markers generated by representational difference analysis

Area of Science:

• Animal Genetics
• Genomics
• Quantitative Trait Loci (QTL) Analysis

Background:

• Selective breeding in Landrace pigs for increased loin muscle area (LMA) results in phenotypic divergence for carcass traits.
• Genetic divergence exists at the skeletal muscle ryanodine receptor 1 locus between selected and control populations.

Purpose of the Study:

• To identify genetic differences between Landrace pig populations selected for high LMA and a control population.
• To develop and map novel sequence-tagged sites (STS) for enhanced pig genome resolution.

Main Methods:

• Representational difference analysis (RDA) was employed using genomic DNA from selected and control Landrace pigs.
• Two RDA experiments (BamHI and BglII) were conducted, followed by cloning, sequencing, and STS development for difference products.
• STS markers were mapped using the INRA-Minnesota porcine Radiation Hybrid panel and integrated into the PiGMaP genetic linkage map.

Main Results:

• Sixteen STS markers were developed from RDA difference products.
• Nine STS markers were successfully mapped to the PiGMaP genetic linkage map, localizing to 11 different porcine chromosomes.
• Significant marker localization occurred on chromosome 11 (three markers) and chromosome 14 (four markers).

Conclusions:

• The developed RDA markers significantly increase the resolution of existing pig genome maps.
• These novel markers, particularly those within QTL regions, can be utilized for fine-mapping and refining the positions of important quantitative trait loci.
• This research contributes to advancing genetic selection strategies in swine breeding programs.