Search

Genetic diversity, population structure, and population expansion of goats worldwide (4 165 individuals from 196 breeds) were analyzed using published mitochondrial DNA (mtDNA) D_loop hypervariable region sequences. Results showed that 2 409 haplotypes and 301 polymorphic sites were present within the 401-bp length D_loop region, the nucleotide diversity (Pi) was 0.03471, and the haplotype diversity (Hd) was 0.9983. Phylogenetic analysis revealed that 98.92% of haplotypes were divided into six obvious clusters, consistent with the classification of the known mitochondrial haplogroups of goats. Haplogroup A accounted for the largest proportion (86%). Interestingly, two unknown divisions (Unknown I and Unknown II) were discovered from goats in Southwest China, suggesting that Southwest China has unique maternal haplogroups. Analysis of molecular variance (AMOVA) and the average number of pairwise differences between populations (PiXY) indicated that geographical variation was small but significant. Neutrality tests (Tajima's D and Fu's FS tests) and mismatch distribution showed that haplogroups B, C, and G had expansion histories. In addition, the phylogenetic relationship between domestic and wild goats suggested that Capra aegagrus is the most likely wild ancestor and may have participated in the domestication of ancestral populations of A, B, C, and F haplogroups. A meta-analysis on the mtDNA sequences of goats from international databases was conducted to analyze goats’ genetic diversity, population structure, and matrilineal system evolution worldwide. The results may help further understand the domestication history and gene flow of goats worldwide.

Abstract The ecotype population of goats (Capra hircus) was created by long‐term artificial selection and natural adaptation. Mile red‐bone goat is an indigenous breed with visible red bones, and its special bone structure has received extensive attention. This study aimed to identify genetic variants and candidate genes associated with specific bone phenotypes using next‐generation sequencing technology (NGS). The results revealed that 31,828,206 single nucleotide polymorphisms (SNPs) were obtained from 72 goats (20 Mile red‐bone goats and 52 common goats) by NGS. A total of 100 candidate genes were identified on the basis top 1% window interaction from nucleotide diversity (π), π ratio (πA/πB), and pairwise fixation index (FST). Exactly 77 known signaling pathways were enriched. Specifically, three coding genes (NMNAT2, LOC102172983, and PNLIP) were annotated in the vitamin metabolism signaling pathways, and NCF2 was annotated to the osteoclast (OC) differentiation pathway. Furthermore, 5862 reliable copy number variations (CNVs) were obtained, and 14 and 24 genes were annotated with the top 1‰ CNV based on FST (>0.490) and VST (>0.527), respectively. Several pathways related to bone development and metabolism of exogenous substances in vivo, including calcium signaling pathway, OC differentiation, and glycerophospholipid metabolism, were annotated. Specifically, six genes from 19 candidate CNVs, which were obtained by interaction of the top 1‰ CNVs with FST and VST, were annotated to mucin‐type O‐glycan biosynthesis and metabolic pathways. Briefly, the results implied that pseudopurpurin and specific genetic variants work together to contribute to the red‐bone color and specific bone structure of Mile red‐bone goat. This study is helpful to understanding the genetic basis of the unique bone phenotype of Mile red‐bone goats.

Background: Polled intersex syndrome (PIS) leads to reproductive disorders in goats and exerts a heavy influence on goat breeding. Since 2001, the core variant of an 11.7 kb deletion at ~129 Mb on chromosome 1 (CHI1) has been widely used as a genetic diagnostic criterion. In 2020, a ~0.48 Mb insertion within the PIS deletion was identified by sequencing in XX intersex goats. However, the suitability of this variation for the diagnosis of intersex goats worldwide and its further molecular genetic mechanism need to be clarified.Results: The whole-genome selective sweep of intersex goats from China was performed with whole-genome next-generation sequencing technology for large sample populations and a case–control study on interbreeds. A series of candidate genes related to the goat intersexuality phenotype were found. We further confirmed that a ~0.48 Mb duplicated fragment (including ERG and KCNJ15) downstream of the ~20 Mb PIS region was reversely inserted into the PIS locus in intersex Chinese goats and was consistent with that in European Saanen and Valais black-necked goats. High-throughput chromosome conformation capture (Hi-C) technology was then used to compare the 3D structures of the PIS variant neighborhood in CHI1 between intersex and non-intersex goats. A newly found structure was validated as an intrachromosomal rearrangement. This inserted duplication changed the original spatial structure of goat CHI1 and caused the appearance of several specific loop structures in the adjacent ~20 kb downstream region of FOXL2.Conclusions: Results suggested that the novel complex PIS variant genome was sufficient as a broad-spectrum clinical diagnostic marker of XX intersexuality in goats from Europe and China. A series of private dense loop structures caused by segment insertion into the PIS deletion might affect the expression of FOXL2 or other neighboring novel candidate genes. However, these structures require further in-depth molecular biological experimental verification. In general, this study provided new insights for future research on the molecular genetic mechanism underlying female-to-male sex reversal in goats.

The objective of the present study was to perform a genome-wide association study (GWAS) for growth curve parameters using nonlinear models that fit original weight–age records. In this study, data from 808 Chinese Simmental beef cattle that were weighed at 0, 6, 12, and 18 months of age were used to fit the growth curve. The Gompertz model showed the highest coefficient of determination (R2 = 0.954). The parameters’ mature body weight (A), time-scale parameter (b), and maturity rate (K) were treated as phenotypes for single-trait GWAS and multi-trait GWAS. In total, 9, 49, and 7 significant SNPs associated with A, b, and K were identified by single-trait GWAS; 22 significant single nucleotide polymorphisms (SNPs) were identified by multi-trait GWAS. Among them, we observed several candidate genes, including PLIN3, KCNS3, TMCO1, PRKAG3, ANGPTL2, IGF-1, SHISA9, and STK3, which were previously reported to associate with growth and development. Further research for these candidate genes may be useful for exploring the full genetic architecture underlying growth and development traits in livestock.

The binder plays a crucial role in binding the solid electrode components and fixing them to the current collector, ensuring good contact and transformation. The high‐energy‐density cathode poses several challenges for the Polyvinylidene fluoride (PVDF) binder, such as high electrode potential, mass loading, and binding force. Although various new binders are proposed to optimize the electrochemical performance of cathode, the design focus and mechanisms often lack universality. This study introduces a design strategy for the cathode binder from the perspective of molecular structure design. The performance of the binder is optimized by adjusting the soft‐hard and hydrophilic‐hydrophobic balances of the polymer, and the effectiveness of this strategy is verified in the LiCoO2 (LCO) system. The optimized copolymer binder improves the cycling stability of the LCO electrode under high load and low binder content conditions and even achieves stable operation at a high charging voltage of 4.6 V. The mechanism for improving the performance of LCO electrodes is that the optimized binder stabilizes the electrode structure, the active material particle structure, and the active material interface. This design strategy provides a valuable reference for customizing cathode binders. [ABSTRACT FROM AUTHOR]

The production of Li2CO3/C through CO2 reduction reaction in nonaqueous systems is a complex four‐electron, multi‐step process, and the short existence time of intermediate monomers is not conducive to observation, which causes great difficulties in clarifying and regulating the CO2 reduction path. Herein, ferrocene (Fc) as a functional additive into the electrolyte can stabilize the discharge intermediates and favor the occurrence of the two‐electron reaction path during CO2RR, which leads to more stable operation of the Li‐CO2 battery; with the assistance of Fc, the CO2 reduction pathway in Li‐CO2 battery is also clarified. Theoretical calculation analysis combined with experimental characterization observation confirms that Fc can shorten the CO2 reduction distance through interaction with CO2 and affecting the solvent environment around Li+, stabilize intermediate products to clarify the discharge path. The existence time of intermediates and discharge depth of the battery are key factors affecting the CO2 reduction pathway. The Li2C2O4 formed by CO2 reduction through the 2‐electron pathway is more favorable for the reversible operation of the Li‐CO2 battery than Li2CO3/C through the 4‐electron pathway. This work provides inspiration for clarifying the reaction mechanism and regulating the CO2 reduction pathway to improve the electrochemical performance of Li‐CO2 battery in the future. [ABSTRACT FROM AUTHOR]

The Boer goat is one of the top meat breeds in modern animal husbandry and has attracted widespread attention for its unique growth performance. However, the genetic basis of muscle development in the Boer goat remains obscure. In this study, we identified specific structural variants in the Boer goat based on genome-wide selection signals and analyzed the basis of the molecular heredity of related candidate genes in muscle development. A total of 9 959 autosomal copy number variations (CNVs) were identified through selection signal analysis in 127 goat genomes. Specifically, we confirmed that the highest signal CNV (HSV) was a chromosomal arrangement containing an approximately 1.11 Mb (CHIR17: 60062304–61171840 bp) duplicated fragment inserted in reverse orientation and a 5 362 bp deleted region (CHIR17:60145940–60151302 bp) with overlapping genes (e.g., ARHGAP10, NR3C2, EDNRA, PRMT9, and TMEM184C). The homozygous duplicated HSV genotype (+/+) was found in 96% of Boer goats but was not detected in Eurasian goats and was only detected in 4% of indigenous African goats. The expression network of three candidate genes (ARHGAP10, NR3C2, and EDNRA) regulating dose transcription was constructed by RNA sequencing. Results indicated that these genes were involved in the proliferation and differentiation of skeletal muscle satellite cells (SMSCs) and their overexpression significantly increased the expression of SAA3. The HSV of the Boer goat contributed to superior skeletal muscle growth via the dose effects of overlapping genes. [ABSTRACT FROM AUTHOR]

Background: Heat stress in domestic animals has become a major limit factor for livestock production in tropical and subtropical regions. These traits that adapt to torrid environment are important in livestock breeding. Methods: In this study, we identified and genotyped six Single nucleotide polymorphism for the CDC37, AHSA1 and STIP1 gene in the Droughtmaster, Angus and Simmental cattle breeds using the SNaPshot Multiplex system. Result: Result of pair-wise differences (FST) revealed three SNP locus (CDC37-6 (A16154247/G), CDC37-7 (C16157867/G), AHSA1- 10 (G89722567/A) were significantly different in the Droughtmaster population than Angus and Simmental cattle breeds. Moreover, it was found that CDC37-7 (C16157867/G) locus deviated from Hardy-Weinberg equilibrium, suggesting that the CDC37-7 (C16157867/ G) genes have been influenced by the selective breeding of the Droughtmaster breed. Therefore, CDC37-7 (C16157867/G) locus could be used as a marker-assisted candidate gene locus of heat tolerance. This study provides valuable information, concerning marker-assisted selection in the breeding of heat stress resistant cattle. [ABSTRACT FROM AUTHOR]