Fat metabolism plays a pivotal role in determining meat quality and economic value in domestic pigs, yet its underlying genetic mechanisms remain poorly understood. To clarify the molecular basis of adipose deposition, this study integrated whole-genome resequencing data from 226 individuals across 61 Eurasian pig breeds and applied population genetic and selective sweep analyses to identify and validate candidate genes involved in fat metabolism. Significant genetic divergence was observed between Asian and European domestic pigs, with higher linkage disequilibrium (LD) levels in domestic breeds likely driven by artificial selection during domestication. High-fat groups (backfat thickness: 39 mm; fat percentage: 35

Cattle are integral to global food security, yet the molecular architecture of their complex traits remains poorly understood. Here, we present the Cattle Genotype–Tissue Expression (CattleG-TEx) Phase 1 resource (https://cattlegtex.farmgtex.org/), a substantial expansion of the pilot study. By leveraging 12,422 RNA-seq profiles across 43 tissues and 82 breeds, we characterized 433,972 primary and 161,428 non-primary regulatory effects spanning seven molecular phenotypes. This high-resolution atlas resolves 75% of GWAS signals for 44 complex traits, significantly addressing the "missing regulation" in livestock. We propose a genetic regulatory model demonstrating how variants across multiple biological layers interact with specific biological contexts to shape pheno-typic variation. Furthermore, CattleGTEx elucidates mechanisms underlying adaptive evolution between Bos taurus and Bos indicus, as well as artificial selection in dairy and beef breeds. Finally, by mapping evolutionary constraints on these regulatory effects, we demonstrate the translational value of this resource for prioritizing causal variants in human complex diseases. Together, Phase 1 of CattleGTEx provides a transformative framework for functional genomics, precision breeding, and comparative genetics.

Characterizing the impact of genomic variants on genome function and ultimately complex traits in livestock is essential for the development of sustainable precision agriculture and comparative genomics. Here, as part of the Farm animal Genotype-Tissue Expression (FarmGTEx) project, we present the pilot phase of the SheepGTEx resource through analyzing 6,761 RNA-sequencing samples of 51 primary tissues in a multi-breed population of sheep. We identify millions of regulatory variants associated with seven types of molecular phenotypes, and fine-map 322,467 primary and 113,968 non-primary effects, revealing a high degree of regulatory allelic heterogeneity. We systematically characterize the pleiotropic effects of these variants on molecular phenotypes, assess their context-specific regulatory patterns across tissues, breeds, sexes, and developmental stages, as well as explore their evolutionary constraints across mammals. Finally, we demonstrate the substantial potential of the SheepGTEx resource (https://sheepgtex.farmgtex.org), by providing examples of regulatory mechanisms underpinning 34 complex traits, population divergence between European and Asian breeds, and adaptive evolution in sheep over the past ten millennia.

The economic efficiency of sheep breeding can be improved by enhancing sheep productivity. A recent genome-wide association study (GWAS) unveiled the potential impact of the MAST4 gene on prolificacy traits in Australian White sheep (AUW)). Herein, whole-genome sequencing (WGS) data from 26 different sheep breeds worldwide (n = 1507), including diverse meat, wool, milk, or dual-purpose sheep breed types from China, Europe, and Africa, were used. Moreover, polymerase chain reaction (PCR) genotyping of the MAST4 gene polymorphisms in (n = 566) Australian white sheep (AUW) was performed. The 3 identified polymorphisms were not homogeneously distributed across the 26 examined sheep breeds. Findings revealed prevalent polymorphisms (P3-ins-29 bp and P6-del-21 bp) with varying frequencies (0.02 to 0.97) across 26 breeds, while P5-del-24 bp was presented in 24 out of 26 breeds. Interestingly, the frequency of the P3-ins-29 bp variant was markedly higher in Chinese meat or dual-purpose sheep breeds, while the other two variants also showed moderate frequencies in meat breeds. Notably, association analysis indicated that all InDels were associated with AUW sheep litter size (p < 0.05). These results suggest that these InDels within the MAST4 gene could be useful in marker-assisted selection in sheep breeding.

全基因组关联分析(GWAS)对畜牧业发展具有重要意义,随着测序技术的发展与分析软件的不断完善,该技术已广泛应用于猪、牛、羊等家畜遗传育种中.科研人员利用GWAS对绵羊群体进行分析,通过在全基因组水平探究影响重要经济性状的基因位点,最终挖掘和标识在育种中有价值的主效基因.本文简要介绍了GWAS的基本流程,重点概述了利用GWAS挖掘影响绵羊重要经济性状的关键基因位点,包括绵羊的产羔数、体重体尺性状、尾脂沉积、脂肪沉积、泌乳性状、角型性状、羊毛性状、相关疾病等性状的研究成果,并对不足之处与未来发展趋势进行总结与展望,以期为我国绵羊产业的发展起到推动作用.

Studying the characteristics of mammalian hoof colors is important for genetic improvements in animals. A deeper black hoof color is the standard for breeding purebred Australian White (AUW) sheep and this phenotype could be used as a phenotypic marker of purebred animals. We conducted a genome-wide association study (GWAS) analysis using restriction site associated DNA sequencing (RAD-seq) data from 577 Australian White sheep (black hoof color = 283, grey hoof color = 106, amber hoof color = 186) and performed association analysis utilizing the mixed linear model in EMMAX. The results of GWAS demonstrated that a specific single-nucleotide polymorphism (SNP; g. 33097911G>A) in intron 14 of the microphthalmia-associated transcription factor (MITF) gene was significantly associated with the hoof color in AUW sheep (p = 9.40 × 10−36). The MITF gene plays a key role in the development, differentiation, and functional regulation of melanocytes. Furthermore, the association between this locus and hoof color was validated in a cohort of 212 individuals (black hoof color = 122, grey hoof color = 38, amber hoof color = 52). The results indicated that the hoof color of AUW sheep with GG, AG, and AA genotypes tended to be black, grey, and amber, respectively. This study provided novel insights into hoof color genetics in AUW sheep, enhancing our comprehension of the genetic mechanisms underlying the diverse range of hoof colors. Our results agree with previous studies and provide molecular markers for marker-assisted selection for hoof color in sheep.

Platelet-derived growth factor (PDGF) family, exert plays a key role in embryonic development, cell proliferation, cell migration, angiogenesis and reproduction. Related studies about GWAS analyses have found that PDGFD significantly affected deposition of tail fat in sheep, but there are no studies on reproduction in animals. In this study, three breed of sheep were used to find insertion/deletion (indel) fragment polymorphism of PDGFD which including Australian white (AUW) sheep (Meat type, n = 932), Guiqian semi-fine wool (GSFW) sheep (wool type, n = 60) and East Friensian milk (EFM) sheep (dairy type, n = 60). Only a 18-bp variation was polymorphic in the study AUW sheep population and the genotypes of different sheep breed are also specific. Moreover, the association analysis indicated that this variant was associated with litter size of AUW sheep in the first parity (p < 0.05). The litter size of II genotype was significantly lower than other genotypes in the first parity (p < 0.05). We also revealed that the PDGFD gene was relatively conservative in eight species, PDGFD mRNA expression in 832 sheep samples implying this gene was related to reproduction traits. Hence, these finding demonstrated the one -cause multipotency of PDGFD gene. Collectively, these results suggest that this indel can be used as an effective marker for sheep breeding.

利用候选基因法和全基因组关联分析法等方法能准确筛选出绵羊生长性状相关的关键基因,挖掘关键基因相关遗传变异位点作为DNA标记进行应用,以提高选择准确性、加快遗传进展.文章综述了正向调控和负向调控基因的研究进展,及其对生长性状的遗传效应,为绵羊生长性状的分子育种提供科学资料.