Related Experiment Video
Updated: Jun 28, 2026

Instrumentation of Near-term Fetal Sheep for Multivariate Chronic Non-anesthetized Recordings
Published on: October 25, 2015
Liver transcriptome analysis reveals sex-dependent genes and gene networks linked to carcass traits in suckling lambs
M Vrcan1, A Suárez-Vega1, P A S Fonseca2
1Departamento de Producción Animal, Facultad de Veterinaria, Universidad de León. Campus de Vegazana, s/n 24007, León, Spain.
Abstract:
Sex is a relevant source of variation in carcass composition in suckling lambs; however, the molecular mechanisms underlying this early sexual dimorphism remain poorly understood. Given the central role of the liver in metabolic regulation and nutrient partitioning, this study characterised sex-specific hepatic transcriptional profiles and their relationship with carcass traits in Assaf suckling lambs. Liver RNA-seq data from 12 lambs (six males and six females) harvested at commercial weight were analysed using differential expression analysis (DEA) and weighted gene co-expression network analysis. Four carcass traits were evaluated: pelvic fat percentage (PFP), muscle percentage (MP), bone percentage (BP), and muscle-to-bone ratio (MP/BP). Females showed higher MP, whereas males had higher PFP, confirming early sexual dimorphism. DEA identified 211 differentially expressed genes, including 93 upregulated in males (M-DEGs) and 118 in females (F-DEGs). M-DEGs genes were enriched in cell cycle and mitotic processes, indicating a more proliferative hepatic profile. F-DEGs were enriched in pathways related to apoptosis, oxidative stress, mitochondrial targeting, and extracellular vesicle components, suggesting a stronger stress-responsive and inter-organ communication profile, possibly linked to the ongoing brown-to-white perirenal adipose tissue transition. Network analysis revealed sex-specific co-expression modules associated with carcass traits, two of which were enriched for DEGs. In males, one of these DEG-enriched modules (green) was negatively associated with PFP, strongly enriched for cell cycle-related functions, and included NDC80 as both a hub gene and M-DEG, supporting a possible link between hepatic proliferative activity and reduced fat deposition. In females, another DEG-enriched module (pink) was negatively associated with BP and positively with MP/BP, with FYN as its top hub gene, highlighting biological processes potentially involved in bone remodelling and muscle growth. Although these results should be considered hypothesis-generating, they indicate that sex-biased hepatic gene networks may be associated with early variation in carcass composition and may support a role for liver-mediated mechanisms in the establishment of postnatal carcass sexual dimorphism in suckling lambs.
Related Concept Videos
Cell Specific Gene Expression
Liver Physiology
Metabolic Regulation:
The liver is the central organ involved in regulating blood composition. It stabilizes blood glucose levels, maintaining them within the range of 70–110 mg/dL. When these levels drop, the liver breaks down glycogen reserves and releases glucose into the bloodstream. It can also...
X-linked Traits
X-linked Traits

