Crossbreeding effect on genome stability in pig (Sus scrofa scrofa)

Area of Science:

• Animal Genetics
• Cytogenetics
• Comparative Genomics

Background:

• Autochthonous pig breeds like Calabrian may possess unique genetic traits.
• Highly selected breeds (LW) often exhibit specific phenotypic and genomic characteristics.
• Heterosis, or hybrid vigor, can influence various traits in crossbred animals.

Purpose of the Study:

• To compare genome stability between Calabrian and LW pig breeds.
• To investigate the influence of heterosis on the genome stability of crossbred pigs.
• To assess chromosomal aberrations (CAs) and sister chromatid exchanges (SCEs) as indicators of genome stability.

Main Methods:

• Cytogenetic analysis was performed on peripheral blood lymphocytes.
• Frequencies of aneuploidy, chromosomal aberrations (CAs), and sister chromatid exchanges (SCEs) were quantified.
• Statistical analysis was used to compare genome stability parameters among the three groups.

Main Results:

• Calabrian pigs exhibited higher mean values for CAs and SCEs compared to LW pigs, with a significant difference in SCEs (P<0.01).
• Crossbred pigs showed genome stability levels comparable to the LW group across most tests, suggesting a positive effect of crossbreeding.
• Aneuploid cell percentages were 7.30% (Calabrian), 10.10% (LW), and 10.79% (crossbred).

Conclusions:

• The Calabrian pig breed may have lower baseline genome stability than the LW breed.
• Crossbreeding appears to enhance genome stability in pigs, potentially due to heterosis.
• These findings contribute to understanding breed-specific genetic stability and the benefits of crossbreeding in swine.