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Breed-specific divergence in boar sperm regulatory profiles involves piRNA and mitochondrial small RNAs
Anna Asratian1, Signe Isacson1, Unn Kugelberg1
1Department of Biomedical and Clinical Sciences, Linköping University, Linköping, Sweden.
Cellular and Molecular Life Sciences : CMLS
|June 4, 2026
Summary
Pig sperm small non-coding RNAs (sRNAs) differ between breeds selected for reproduction versus meat production. Reproductive breeds show high PIWI-interacting RNA (piRNA) variability, while meat breeds have more mitochondrial ribosomal RNA-derived sRNAs (mt rsRNAs).
Area of Science:
- Epigenetics
- Animal Genomics
- Reproductive Biology
Background:
- Small non-coding RNAs (sRNAs) regulate gene expression and protect genomic integrity.
- Sperm sRNA profiles can be influenced by environmental factors and genetic variations, impacting offspring traits.
- Selective breeding in commercial pigs has led to divergent traits, such as meat production versus reproductive capacity.
Purpose of the Study:
- To characterize and compare the sperm sRNA composition across four commercial pig breeds with distinct breeding objectives (meat production vs. reproductive capacity).
- To investigate potential epigenetic mechanisms related to sRNA profiles that influence breeding outcomes.
Main Methods:
- Analysis of sperm small non-coding RNA (sRNA) composition.
- Comparison of sRNA profiles between two meat production breeds (Duroc, Hampshire) and two reproductive breeds (Landrace, Yorkshire).
- Identification of specific sRNA types, including PIWI-interacting RNAs (piRNAs) and mitochondrial ribosomal RNA-derived sRNAs (mt rsRNAs), and microRNAs (miRNAs).
Main Results:
- Reproductive breeds (Landrace, Yorkshire) exhibited high variability in PIWI-interacting RNAs (piRNAs), which are crucial for transposable element regulation.
- Meat production breeds (Duroc, Hampshire) showed enrichment in mitochondrial ribosomal RNA-derived sRNAs (mt rsRNAs), potentially linked to metabolic functions.
- Significant differences in microRNA (miRNA) profiles were observed, associated with developmental and metabolic processes.
Conclusions:
- Sperm sRNA profiles in pigs are associated with specific breeding objectives, suggesting adaptive epigenetic strategies.
- Reproductive breeds may prioritize genome protection (via piRNAs), while meat breeds focus on mitochondrial function (via mt rsRNAs).
- These findings offer insights into epigenetic mechanisms that could be utilized in selective breeding for improved fertility, growth, and offspring health.
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