• Asian-Australasian Journal of Animal Sciences
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• 제33권9호
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• pp.1369-1377
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• 2020

Objective: The main objectives of the present study were to assess the genetic diversity, population structure and to appraise the efficiency of ongoing selective breeding program in the closed nucleus herd of Nellore sheep through pedigree analysis. Methods: Information utilized in the study was collected from the pedigree records of Livestock Research Station, Palamaner during the period from 1989 to 2016. Genealogical parameters like generation interval, pedigree completeness, inbreeding level, average relatedness among the animals and genetic conservation index were estimated based on gene origin probabilities. Lambs born during 2012 and 2016 were considered as reference population. Two animal models either with the use of F_i or ΔF_i as linear co-variables were evaluated to know the effects of inbreeding on the growth traits of Nellore sheep. Results: Average generation interval and realized effective population size for the reference cohort were estimated as 3.38±0.10 and 91.56±1.58, respectively and the average inbreeding coefficient for reference population was 3.32%. Similarly, the effective number of founders, ancestors and founder genome equivalent of the reference population were observed as 47, 37, and 22.48, respectively. Fifty per cent of the genetic variability was explained by 14 influential ancestors in the reference cohort. The ratio f_e/f_a obtained in the study was 1.21, which is an indicator of bottlenecks in the population. The number of equivalent generations obtained in the study was 4.23 and this estimate suggested the fair depth of the pedigree. Conclusion: Study suggested that the population had decent levels of genetic diversity and a non-significant influence of inbreeding coefficient on growth traits of Nellore lambs. However, small portion of genetic diversity was lost due to a disproportionate contribution of founders and bottlenecks. Hence, breeding strategies which improve the genetic gain, widens the selection process and with optimum levels of inbreeding are recommended for the herd.

• Animal Bioscience
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• 제36권5호
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• pp.692-703
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• 2023

Objective: The main goals of this investigation were to i) assess the population structure and genetic diversity and ii) determine the efficiency of the ongoing breeding program in a closed flock of Angora rabbits through pedigree analysis. Methods: The pedigree records of 6,145 animals, born between 1996 to 2020 at NTRS, ICAR-CSWRI, Garsa were analyzed using ENDOG version 4.8 software package. The genealogical information, genetic conservation index and parameters based on gene origin probabilities were estimated. Results: Analysis revealed that, 99.09% of the kits had both parents recorded in the whole dataset. The completeness levels for the whole pedigree were 99.12%, 97.12%, 90.66%, 82.49%, and 74.11% for the 1st, 2nd, 3rd, 4th, and 5th generations, respectively, reflecting well-maintained pedigree records. The maximum inbreeding, average inbreeding and relatedness were 36.96%, 8.07%, and 15.82%, respectively. The mean maximum, mean equivalent and mean completed generations were 10.28, 7.91, and 5.51 with 0.85%, 1.19%, and 1.85% increase in inbreeding, respectively. The effective population size estimated from maximum, equivalent and complete generations were 58.50, 27.05, and 42.08, respectively. Only 1.51% of total mating was highly inbred. The effective population size computed via the individual increase in inbreeding was 42.83. The effective numbers of founders (f_e), ancestors (f_a), founder genomes (f_g) and non-founder genomes (f_ng) were 18, 16, 6.22, and 9.50, respectively. The fe/fa ratio was 1.12, indicating occasional bottlenecks had occurred in the population. The six most influential ancestors explained 50% of genes contributed to the gene pool. The average generation interval was 1.51 years and was longer for the sire-offspring pathway. The population lost 8% genetic diversity over time, however, considerable genetic variability still existed in the closed Angora population. Conclusion: This study provides important and practical insights to manage and maintain the genetic variability within the individual flock and the entire population.

• Biotechnology and Bioprocess Engineering:BBE
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• 제5권2호
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• pp.71-78
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• 2000

The recent progress od DNA technologies including DNA fingerprinting (DFP) and random amplified DNA polymorphism (RAPD) analysis make it possible to identify the specific genetic trits of animals and to analyze the genetic diversity and relatedness between or withinspecies or populations. Using those techniquse, some efforts to identify and develop the specific DNA markers based on DNA polymorphism, which are related with economic traits for Korean native animals, Hanwoo(Korean native cattle),Korean native pig and Korean native chicken, have been made in Korea for recent a few years. The developed specific DNA markers successfully characterize the Korean native animals as the unique Korean genetic sources, distinctively from other imported breeds. Some of these DNA markers have been related to some important economic traits for domestic animals, for example, growth rate and marbling for Honwoo, growth rate and back fat thinkness fornative pig, and growth rate, agg weight and agg productivity for native chicken. This means that those markers can be used in important marker-assised selection (MAS) of Korean native domestic animals and further contribute to genetically improve and breed them.

• BMB Reports
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• 제46권6호
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• pp.305-309
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• 2013

The determination of relatedness between individuals in a family is crucial in analysis of common complex diseases. We present a method to infer close inter-familial relationships based on SNP genotyping data and provide the relationship coefficient of kinship in Korean families. We obtained blood samples from 43 Korean individuals in two families. SNP data was obtained using the Affymetrix Genome-wide Human SNP array 6.0 and the Illumina Human 1M-Duo chip. To measure the kinship coefficient with the SNP genotyping data, we considered all possible pairs of individuals in each family. The genetic distance between two individuals in a pair was determined using the allele sharing distance method. The results show that genetic distance is proportional to the kinship coefficient and that a close degree of kinship can be confirmed with SNP genotyping data. This study represents the first attempt to identify the genetic distance between very closely related individuals.

• Parasites, Hosts and Diseases
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• 제44권2호
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• pp.117-125
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• 2006

Genetic diversity of 18 Acanthamoeba isolates from ocean sediments was evaluated by comparing mitochondrial (mt) DNA RFLP, 18S rDNA sequences and by examining their cytopathic effects on human corneal epithelial cells versus reference strains. All isolates belonged to morphologic group II. Total of 16 restriction phenotypes of mtDNA from 18 isolates demonstrated the genetic diversity of Acanthamoeba in ocean sediments. Phylogenetic analysis using 18s rDNA sequences revealed that the 18 isolates were distinct from morphological groups I and III. Fifteen isolates showed close relatedness with 17 clinical isolates and A. castellanii Castellani and formed a lineage equivalent to T4 genotype of Byers' group. Two reference strains from ocean sediment, A. hatchetti BH-2 and A. griffini S-7 clustered unequivocally with these 15 isolates. Diversity among isolates was also evident from their cytopathic effects on human corneal cells. This is the first time describing Acanthamoeba diversity in ocean sediments in Korea.

• Journal of Forest and Environmental Science
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• 제35권2호
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• pp.90-101
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• 2019

Biodiversity refers to the total number and variation among species of flora and fauna of an area. Due to tremendous biotic especially anthropogenic pressure these natural resources are being vanishing. In present study genetic diversity among accessions of Thamnocalamus spathiflorus was evaluated. A total of 51 vegetative characters and 42 primers (10-mer) were screened. Out of 42 screened primers, 28 polymorphic primers were selected for further analysis. A total of 263 bands were recorded as polymorphic whereas 48 bands were monomorphic. The resolving power (Rp) of 28 Randomly Amplified Polymorphic DNA (RAPD) primers ranged from 4.6 (OPE08) to 17.6 (OPA11). The polymorphic information content (PIC) value ranged from 0.21 (OPAH09) to 0.44 (OPG02). The result revealed high degree of genetic relatedness (56 to 80%). Cluster analysis revealed two major clusters both for morphology as well as RAPD. Unlike morphological characterization, the accession (D5) from Bahli, Rampur, Shimla (H.P.) was clustered separately from the others in RAPD cluster analysis. Accessions with closed locality grouped together through RAPD marker system however analogy was recorded for morphological traits. The study conducted reflects the utility of RAPD technique for species identification and phylogenetic studies in bamboo for conducting bamboo breeding program.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.217-217
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• 2022

Pullulanase (PUL), a debranching enzyme, has been utilized in hydrolyzing the a-1,6 glucosidic linkages in starch, amylopectin, pullulan, as well as related oligosaccharides. It has also been indicated that PUL is a novel indicator of inherent RS (Resistant Starch) formation in rice. In this study, we performed haplotype analysis on 320 bred rice accessions, and additional 54 wild accessions were added to study genetic diversity along with other population-based analyses of the PUL gene. Through these investigations, we summarized a total of 10 functional (non-synonymous) SNPs from 7 different exons on chromosome 4. There were 10 haplotypes, of which only six haplotypes were functional, implicating different subpopulations. Diversity reduction was noticed in temperate japonica (0.0005) compared to the highest one (aus, 0.0154), illustrating their higher genetic differentiation by F_ST-value (0.926). The highest Tajima^ D value was observed in indica (3.6613), indicating PUL gene domestication signature under balancing selection, while the lowest Tajima's D value was found in temperate japonica (-2.2191) which might have undergone under positive selection and purified due to the excess of rare alleles. PCA, population structure, and phylogenetic analyses provide information on the genetic relatedness between and or among the cultivated subpopulations and the wild based on PUL genomic region.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2018년도 추계학술대회
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• pp.74-74
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• 2018

Little millet (Panicum sumatrense) is well known for its salt and drought stress tolerance and high nutritional value, but very limited knowledge of genetic variation and genomic information is available. This study was to develop highly polymorphic EST-SSR markers based on cross-species transferability of derived SSRs from switchgrass EST databases and characterize newly developed EST - SSRs to better understand the genetic diversity of collected 37 germplasm accessions of little millet. A total of 779 primer pairs were designed from the 22,961 EST sequences of switchgrass (Pancium virgatum), of which 48 EST - SSR markers were developed based on the trials of transferability of these primers in little millet. The EST - SSR amplicons showed reproducible single band polymorphism and produced a total of 160 alleles with an average of 3.3 alleles per locus in 37 accessions of little millet. T he average values of expected and observed heterozygosities were 0.266 and 0.123, respectively. T he polymorphic information content (PIC) values were observed in range of 0.026 to 0.549 with an average of 0.240. The genetic relatedness among the little millet accessions was evaluated by neighbor-joining dendrogram, which grouped all accessions into two distinct groups. The validation thus demonstrated the utility of the switchgrass EST - SSR markers in assessing genomic relationships in little millet. T he findings from this study could be useful for designing strategies for the identification of diverse germplasm for conservation and future molecular breeding programs for little millet.

• 한국어병학회지
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• 제24권1호
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• pp.1-9
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• 2011

Viral haemorrhagic septicaemia virus (VHSV) is an epidemic virus in olive flounder Paralichthys olivaceus farms in Korea, since the virus have first isolated in 2001. In the present study, partial glycoprotein (G) gene nucleotide sequences of seven Korean VHSV from cultured olive flounder and wild marine fishes in coastal areas of Korea were analyzed to evaluate their genetic relatedness to worldwide isolates. Phylogenetically, all Korean VHSV formed only one minor cluster including Japanese isolates, in genotype IVa, while the North America isolates formed a different minor cluster in genotype IVa. These results suggest that Korean VHSV could be an indigenous virus in Korean and Japanese coastal areas, but have not been introduced from North America.

• 한국동물학회지
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• 제31권1호
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• pp.1-10
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• 1988

자매종 R.nigromaculate(참개구리)와 R. plancyi(금개구리)간의 생식적 격리기작을 구명하기 위하여 전라남도 광주시에서 발견된 자연집중 1개체를 포함한 두 종의 형태, 유전적 변이 및 번식시기 등을 조사한 분석한 결과는 다음과 같다. 두 종은 형태,유전,mating call 및 번식시기 등에 뚜렷한 차이가 있었고, 약 350만년 전에 남방계인 R. plancyi에서 R.nigromaculate가 분화되었을 것으로 추정되었다. 잡종 1개체는 전기영동 결과 일대잡종으로 확인되었으며 포란한 정상 난소를 갖고 있는 점으로 미루어 보아 생식이 간으하다고 여기지며, 따라서 postmating isolating mechanism은 불완전하게 생성되었다고 추측된다.