• Asian-Australasian Journal of Animal Sciences
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• 제33권1호
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• pp.12-23
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• 2020

Objective: The objective of a conservation program is to maintain maximum genetic diversity and preserve the viability of a breed. However, the efficiency of a program is influenced by the ability to accurately measure and predict genetic diversity. Methods: To examine this question, we conducted a simulation in which common measures (i.e. heterozygosity) and novel measures (identity-by-descent probabilities and parental genomic components) were used to estimate genetic diversity within a conserved population using double-labeled single nucleotide polymorphism markers. Results: The results showed that the accuracy and sensitivity of identity-by-state probabilities and heterozygosity were close to identity by descent (IBD) probabilities, which reflect the true genetic diversity. Expected heterozygosity most closely aligned with IBD. All common measures suggested that practices used in the current Chinese pig conservation program result in a ~5% loss in genetic diversity every 10 generations. Parental genomic components were also analyzed to monitor real-time changes in genomic components for each male and female ancestor. The analysis showed that ~7.5% of male families and ~30% of female families were lost every 5 generations. After 50 generations of simulated conservation, 4 male families lost ~50% of their initial genomic components, and the genomic components for 24.8% of the female families were lost entirely. Conclusion: In summary, compared with the true genetic diversity value obtained using double-labeled markers, expected heterozygosity appears to be the optimal indicator. Parental genomic components analysis provides a more detailed picture of genetic diversity and can be used to guide conservation management practices.

• Journal of Microbiology and Biotechnology
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• 제22권1호
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• pp.13-24
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• 2012

The genetic diversity of plant growth-promoting rhizobacterial (PGPR) fluorescent pseudomonads associated with the sugarcane (Saccharum officinarum L.) rhizosphere was analyzed. Selected isolates were screened for plant growthpromoting properties including production of indole acetic acid, phosphate solubilization, denitrification ability, and production of antifungal metabolites. Furthermore, 16S rDNA sequence analysis was performed to identify and differentiate these isolates. Based on 16S rDNA sequence similarity, the isolates were designated as Pseudomonas plecoglossicida, P. fluorescens, P. libaniensis, and P. aeruginosa. Differentiation of isolates belonging to the same group was achieved through different genomic DNA fingerprinting techniques, including randomly amplified polymorphic DNA (RAPD), amplified ribosomal DNA restriction analysis (ARDRA), repetitive extragenic palindromic (REP), enterobacterial repetitive intergenic consensus (ERIC), and bacterial repetitive BOX elements (BOX) analyses. The genetic diversity observed among the isolates and rep-PCR-generated fingerprinting patterns revealed that PGPR fluorescent pseudomonads are associated with the rhizosphere of sugarcane and that P. plecoglossicida is a dominant species. The knowledge obtained herein regarding the genetic and functional diversity of fluorescent pseudomonads associated with the sugarcane rhizosphere is useful for understanding their ecological role and potential utilization in sustainable agriculture.

• 대한미생물학회지
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• 제34권6호
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• pp.519-532
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• 1999

Helicobacter pylori is a causative agent of type B gastritis and plays a central role in the pathogenesis of gastroduodenal ulcer and gastric cancer. To elucidate the host-parasite relationship of the H. pylori infection on the basis of molecular biology, we tried to evaluate the genomic diversity of H. pylori. An ordered overlapping bacterial artificial chromosome (BAC) library of a Korean isolate, H. pylori 51 was constructed to set up a genomic map. A circular physical map was constructed by aligning ApaI, NotI and SfiI-digested chromosomal DNA. When the physical map of H. pylori 51 was compared to that of unrelated strain, H. pylori 26695, completely different restriction patterns were shown. Fifteen known genes were mapped on the chromosome of H. pylori 51 and the genetic map was compared with those of strain 26695 and J99, of which the entire genomic sequences were reported. There were some variability in the gene location as well as gene order among three strains. For further analysis on the genomic diversity of H. pylori, when comparing the genomic structure of 150 H. pylori Korean isolates with one another, genomic macrodiversity of H. pylori was characterized by several features: whether or not susceptible to restriction digestion of the chromsome, variation in chromosomal restriction fingerprint and/or high frequency of gene rearrangement. We also examined the extent of allelic variation in nucleotide or deduced amino acid sequences at the individual gene level. fucT, cagA and vacA were confirmed to carry regions of high variation in nucleotide sequence among strains. The plasticity zone and strain-specific genes of H. pylori 51 were analyzed and compared with the former two genomic sequences. It should be noted that the H. pylori 51-specific sequences were dispersed on the chromosome, not congregated in the plasticity zone unlike J99- or 26695-specific genes, suggesting the high frequency of gene rearrangement in H. pylori genome. The genome of H. pylori 51 shows differences in the overall genomic organization, gene order, and even in the nucleotide sequences among the H. pylori strains, which are far greater than the differences reported on the genomic diversity of H. pylori.

• Animal Bioscience
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• 제37권3호
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• pp.461-470
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• 2024

Objective: The objective of this study was to investigate the genetic diversity, population structure and whole-genome selection signatures of Luxi cattle to reveal its genomic characteristics in terms of meat and carcass traits, skeletal muscle development, body size, and other traits. Methods: To further analyze the genomic characteristics of Luxi cattle, this study sequenced the whole-genome of 16 individuals from the core conservation farm in Shandong region, and collected 174 published genomes of cattle for conjoint analysis. Furthermore, three different statistics (pi, F_st, and XP-EHH) were used to detect potential positive selection signatures related to selection in Luxi cattle. Moreover, gene ontology and Kyoto encyclopedia of genes and genomes pathway enrichment analyses were performed to reveal the potential biological function of candidate genes harbored in selected regions. Results: The results showed that Luxi cattle had high genomic diversity and low inbreeding levels. Using three complementary methods (pi, F_st, and XP-EHH) to detect the signatures of selection in the Luxi cattle genome, there were 2,941, 2,221 and 1,304 potentially selected genes identified, respectively. Furthermore, there were 45 genes annotated in common overlapping genomic regions covered 0.723 Mb, including PLAG1 zinc finger (PLAG1), dedicator of cytokinesis 3 (DOCK3), ephrin A2 (EFNA2), DAZ associated protein 1 (DAZAP1), Ral GTPase activating protein catalytic subunit alpha 1 (RALGAPA1), mediator complex subunit 13 (MED13), and decaprenyl diphosphate synthase subunit 2 (PDSS2), most of which were enriched in pathways related to muscle growth and differentiation and immunity. Conclusion: In this study, we provided a series of genes associated with important economic traits were found in positive selection regions, and a scientific basis for the scientific conservation and genetic improvement of Luxi cattle.

• Animal Bioscience
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• 제37권4호
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• pp.591-599
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• 2024

Objective: Sumba Ongole (SO) cattle are valuable breed due to their important role in the development of Indonesian cattle. Despite rapid advances in molecular technology, no genomic studies on SO cattle have been conducted to date. The aim of this study is to provide genomic profile related to the population diversity, admixture, and demographic trends of SO cattle. Methods: Genomic information was gathered from 79 SO cattle using the Illumina Bovine SNP50 v3 Beadchip, and for comparative purposes, additional genotypes from 209 cattle populations worldwide were included. The expected and observed heterozygosity, inbreeding coefficient, pairwise fixation indices between-population, and Nei's genetic distance were examined. Multidimensional scaling, admixture, and treemix analyses were used to investigate the population structure. Based on linkage disequilibrium and effective population size calculations, the demographic trend was observed. Results: The findings indicated that the genetic diversity of SO cattle was similar to that of other indicine breeds. SO cattle were genetically related to indicines but not to taurines or Bali cattle. The study further confirmed the close relationship between SO, Ongole, and Nellore cattle. Additionally, a small portion of the Ongole mixture were identified dominant in the SO population at the moment. The study also discovered that SO and Bali cattle (Bos javanicus) could have been ancestors in the development of Ongole Grade cattle, which corresponds to the documented history of Ongolization. Our finding indicate that SO cattle have maintained stability and possess unique traits separate from their ancestors. Conclusion: In conclusion, the genetic diversity of the SO cattle has been conserved as a result of the growing significance of the present demographic trend. Consistent endeavors are necessary to uphold the fitness of the breed.

• Genomics & Informatics
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• 제12권4호
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• pp.136-144
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• 2014

Besides single-nucleotide variants in the human genome, large-scale genomic variants, such as copy number variations (CNVs), are being increasingly discovered as a genetic source of human diversity and the pathogenic factors of diseases. Recent experimental findings have shed light on the links between different genome architectures and CNV mutagenesis. In this review, we summarize various genomic features and discuss their contributions to CNV formation. Genomic repeats, including both low-copy and high-copy repeats, play important roles in CNV instability, which was initially known as DNA recombination events. Furthermore, it has been found that human genomic repeats can also induce DNA replication errors and consequently result in CNV mutations. Some recent studies showed that DNA replication timing, which reflects the high-order information of genomic organization, is involved in human CNV mutations. Our review highlights that genome architecture, from DNA sequence to high-order genomic organization, is an important molecular factor in CNV mutagenesis and human genomic instability.

• Asian-Australasian Journal of Animal Sciences
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• 제32권8호
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• pp.1069-1076
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• 2019

Objective: Yunnan is not only a frontier zone that connects China with South and Southeast Asia, but also represents an admixture zone between taurine (Bos taurus) and zebu (Bos indicus) cattle. The purpose of this study is to understand the level of genomic diversity and the extent of admixture in each Yunnan native cattle breed. Methods: All 120 individuals were genotyped using Illumina BovineHD BeadChip (777,962 single nucleotide polymorphisms [SNPs]). Quality control and genomic diversity indexes were calculated using PLINK software. The principal component analysis (PCA) was assessed using SMARTPCA program implemented in EIGENSOFT software. The ADMIXTURE software was used to reveal admixture patterns among breeds. Results: A total of 604,630 SNPs was obtained after quality control procedures. Among six breeds, the highest level of mean heterozygosity was found in Zhaotong cattle from Northeastern Yunnan, whereas the lowest level of heterozygosity was detected in Dehong humped cattle from Western Yunnan. The PCA based on a pruned dataset of 233,788 SNPs clearly separated Dehong humped cattle (supposed to be a pure zebu breed) from other five breeds. The admixture analysis further revealed two clusters (K = 2 with the lowest cross validation error), corresponding to taurine and zebu cattle lineages. All six breeds except for Dehong humped cattle showed different degrees of admixture between taurine and zebu cattle. As expected, Dehong humped cattle showed no signature of taurine cattle influence. Conclusion: Overall, considerable genomic diversity was found in six Yunnan native cattle breeds except for Dehong humped cattle from Western Yunnan. Dehong humped cattle is a pure zebu breed, while other five breeds had admixed origins with different extents of admixture between taurine and zebu cattle. Such admixture by crossbreeding between zebu and taurine cattle facilitated the spread of zebu cattle from tropical and subtropical regions to other highland regions in Yunnan.

• 한국가금학회지
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• 제37권4호
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• pp.355-360
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• 2010

본 연구는 국내에 보급되고 있는 대표적인 토종닭 브랜드인 한협3호와 농촌진흥청에서 개발된 브랜드인 우리맛닭, 두 브랜드 집단 간의 유전적 특성을 분석하여 향후 브랜드간의 차별화 전략을 구체화 하는데 있어 기초 자료로 활용하고자 실시하였다. 토종닭 실용계인 우리맛닭(W) 152수와 한협3호(H) 150수, 총 302수를 선발하여 공시재료로 활용하였으며, 다형성이 확인된 10종의 MS marker를 선발하여 활용하였다. 분석 결과, 두 브랜드의 평균 대립유전자의 수는 9.3으로 확인되었으며, 우리맛닭의 평균 대립유전자의 수는 8.4개, 한협3호는 7.2개로 우리맛닭이 보유한 대립유전자의 수가 많은 것으로 확인되었다. 반면, 기대되는 이형접합도(Ex H)와 관측된 이형접합도(Ob H)는 한협3호가 우리맛닭에 비해 높은 것으로 확인되었다. 두 브랜드 집단을 대상으로 각각의 MS marker의 유전자형을 분석하여 브랜드별 기대되는 이형접합도(expected heterozygosity: Ex H)와 관측된 이형접합도(observed heterozygosity: Ob H) 및 PIC(polymorphism information content)값을 계산하였다. 두 브랜드 집단 간의 유전적 유연관계를 분석 결과, DA distance는 0.132, 그리고 standard genetic distance는 0.199로 확인되었다. 두 브랜드 집단 간의 유전적 구조에 따라 각 개체들이 어떻게 분포되어 있는가를 확인한 결과, 두 집단에 속한 개체들은 크게 두 개의 그룹으로 나뉘어 분포하고 있음을 확인할 수 있었다. 두 집단 간의 유전적 거리는 비교적 가깝지만 각 개체들간의 유전적 구조를 분석한 결과, 확연히 구분되는 유전적 특성을 지니고 있음을 확인하였다.

• 한국식물병리학회지
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• 제14권2호
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• pp.171-176
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• 1998

Gentic diversity of 42 isolates of Phomopsis citri was analyzed with random amplified polymorphic DNA(RAPD) and fungicide resistance. RAPD profiles of genomic DNA of the isolates of P. citri and the degrees of their resistance to the fungicides mancozeb and propineb suggested the occurrence of genetic differentiation of P. citri distributed in Cheju. The isolates showed genetically diverse RAPD profiles according to the host species collected even from the same collection site and also according to the geographic origin collected even from the same host species. High levels of resistance to fungicides mancozeb and propineb were observed among the isolates of P. citri. However, there was no correlation between RAPD profiles of genomic DNA and levels of fungicide resistance of the isolates, suggesting that fungicide resistance of P. citri occurred irrespective of the host and geographic origin.

• 한국균학회지
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• 제30권1호
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• pp.66-72
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• 2002

Phytophthora capsici 집단의 유전적 특성 분석용 DNA marker를 선발하고자 HindIII로 처리된 P. capsici 95CY3119 균주의 genomic DNA library를 임의로 cloning 시킨 후 southern blot 분석을 실시하여 선발된 clone들의 특성을 조사하였다. Probe로 사용하기 위해 선발된 clone 내에 삽입된 DNA 단편들은 HindIII로 처리된 P. capsici 95CY3119의 genomic DNA와 특이적으로 강하게 반응했다. 조사된 probe 중 PC9은 HindIII로 처리된 국내 P. capsici 균주들의 genomic DNA와 Southern 분석시 많은 밴드를 형성하였으며, 분리포장 단위별 균주들 간에는 물론 동일 포장 분리균주들 간에도 그 차이를 나타냈다. 그 밴드 양상을 기초로 집괴분석을 실시한 결과, 각 균주의 유전적 다양성이 잘 나타났다. Prove PC22는 다른 Phytophthora속과 Pythium속 균주들의 genomic DNA들과의 Southern hybridization에서는 반응을 나타내지 않았지만 특이적으로 P. capsici 균주들과는 다수의 밴드를 형성하였다. 이들 P. capsici 종특이적 DNA probe들은 추후 국내 및 전세계에 분포하는 P. capsici 집단의 유전적 다양성 분석 및 종동정에 유용한 marker로서 활용될 수 있을 것이다.