• Asian-Australasian Journal of Animal Sciences
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• v.14 no.5
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• pp.597-602
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• 2001

This study was conducted to examine the relationships between the methods used to determine the number of transferable embryos collected per flush and the estimated cumulative genetic improvements in the Japanese Holstein MOET breeding population. Cumulative genetic improvements were predicted by Monte Carlo simulation using three different determination methods (MODEL 1, MODEL 2, and MODEL 3), for calculating the number of embryos collected per flush. Moreover EBVs were estimated including or ignoring coefficients of inbreeding in MME. Inbreeding coefficients were also predicted. The number of transferable embryos was determined using normal, gamma, and Poisson distributions in MODEL 1, gamma and Poisson distributions in MODEL 2, and only the Poisson distribution in MODEL 3. The fitness of MODEL 2 in relation to field data from Hokkaido Japan was the best, and the results for MODEL3 indicated that this model is unsuitable for determining the number of transferable embryos. The largest cumulative genetic improvement (3.11) in the 10th generation was predicted by MODEL 3 and the smallest (2.83) by MODEL 2. Mean coefficients of correlation between the true and estimated breeding values were 0.738, 0.729, and 0.773 in MODELS 1, 2, and 3, respectively. It is suggested that the smallest genetic improvement in MODEL 2 resulted from the smallest correlation coefficient between the true and estimated breeding values. The differences in milk, fat, and protein yields between MODELS 2 and 3 were 182.0, 7.0, and 5.6 kg, respectively, in real units when each trait was independently selected. The inbreeding coefficient was the highest (0.374) in MODEL 2 and the lowest (0.357) in MODEL 3. The effects of different methods for determining the number of transferable embryos per flush on genetic improvements and inbreeding coefficients of the simulated populations were remarkable. The effects of including coefficients of inbreeding in MME, however, were unclear.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.11
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• pp.1546-1550
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• 2006

The purpose of this study was to assess the genetic variation and establish the relationship amongst breeds and strains using 15 chicken specific microsatellite markers. A total of 285 unrelated DNA samples from four Korean native chicken strains (Black strain of Korean native chicken; KL, Red Brown strain of Korean native chicken; KR, Ogol strain of Korean native chicken; KS and Yellow Brown strain of Korean native chicken; KY) and three introduced chicken breeds (F strain of White Leghorn; LF, K strain of White Leghorn; LK, Rhode Island Red; RC and Cornish; CN) were genotyped to estimate within and between breed genetic diversity indices. All the loci analyzed in 15 microsatellite markers showed a polymorphic pattern and the number of alleles ranged from 5 to 14. The polymorphism information content (PIC) of UMA1019 was the highest (0.872) and that of ADL0234 was the lowest (0.562). The expected total heterozygosity (He) within breed and mean number of observed alleles ranged from 0.540 (LF) to 0.689 (KY), and from 3.47 (LK) to 6.07 (KR), respectively. The genetic variation of KR and KY were the highest and the lowest within Korean native strains, respectively. The genetic distance results showed that Korean native chicken strains were separated with the three introduced chicken breeds clustered into another group. The lowest distance (0.149) was observed between the KR and KL breeds and the highest distance (0.855) between the KR and LK breeds. The microsatellite polymorphism data were shown to be useful for assessing the genetic relationship between Korean native strains and other foreign breeds.

• Animal Systematics, Evolution and Diversity
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• v.13 no.3
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• pp.233-246
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• 1997

A genetic analysis using starch gel electrophoresis was performed to clarify the degrees of genetic differentiation and the phylogenetic relationships among four species of the genus Corbicula (Bivalvia, Corbiculidae). The average genetic similarity coefficients among the populations of each species on C. fluminea, C. leana and C. colorata were very closed (Rogers' S$\geq$0.970), whereas the other C. japonica was separated into two genetic groups (S=0.873) with distinct allelic difference at the Gpl locus. Thuefore additional taxonomic studies are needed on this species. On the other hand, these four species were well distinguished from each other genetically with distinct allelic differences at 4 to 9 loci. The genetic similarity coefficients (S) between C. leana and C. colorata, C. fluminea and C. leana, and C. fluminea and C. colorata were 0.737, 0.689, and 0.594, respectively. In particular, the average genetic similarity coefficients between these three species (inhabiting in freshwater) and the other C. japonica (inhabiting in brackishwater) were notably lower (S=0.370).

• KOREAN JOURNAL OF CROP SCIENCE
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• v.46 no.2
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• pp.112-120
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• 2001

Genetic diversity of 47 East-Asian vegetable soybean was characterized by means of agro-morphological traits and RAPD markers. A field trial was conducted to evaluate 14 agro-morphological traits. To study RAPD-based DNA analysis, a total of sixty 10-mer random primers were screened. Of these, 23 polymorphic markers in 16 varieties used for screening. Among 207 markers amplified, 48 were polymorphic for at least one pairwise comparison within the 47 varieties. A higher differentiation level between varieties was observed by using RAPD markers compared to morphological markers. Correspondence analysis using both types of marker showed that RAPD data could fully discriminate between all varieties, whereas morphological markers could not achieve a complete discrimination. Genetic distances between the varieties were estimated from simple matching coefficients, ranged from 0.0 to 0.640 with an average of 0.295$\pm$0.131 for morphological traits and 0.042 to 0.625 with an average of 0.336$\pm$0.099 for RAPD data, respectively. Cluster analysis based on genetic dissimilarity of these varieties gave rise to 4 distinct groups. The clustering results based on RAPDs did not match with those based on morphological traits. Geographical distribution of most varieties in each of the groups were not well defined. The results suggested that the level of genetic diversity within this group of East-Asian vegetable soybean varieties was sufficient for a breeding program and can be used to establish genetic relationships among them with unknown or unrelated pedigrees.

• Journal of Plant Biotechnology
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• v.43 no.2
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• pp.181-188
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• 2016

In this study, we developed 15 novel polymorphic simple sequence repeat (SSR) markers by SSR-enriched genomic library construction from Codonopsis lanceolata. We obtained a total of 226 non-redundant contig sequences from the assembly process and designed primer sets. These markers were applied to 53 accessions representing the cultivated C. lanceolata in South Korea. Fifteen markers were sufficiently polymorphic, and were used to analyze the genetic relationships between the cultivated C. lanceolata. One hundred three alleles of the 15 SSR markers ranged from 3 to 19 alleles at each locus, with an average of 6.87. By cluster analysis, we detected clear genetic differences in most of the accessions, with genetic distance varying from 0.73 to 0.93. Phylogenic analysis indicated that the accessions that were collected from the same area were distributed evenly in the phylogenetic tree. These results indicate that there is no correlative genetic relationship between geographic areas. These markers will be useful in differentiating C. lanceolata genetic resources and in selecting suitable lines for a systemic breeding program.

• Journal of Plant Biotechnology
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• v.44 no.3
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• pp.243-263
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• 2017

This study is to establish the varietal discrimination based on DNA profiling of different varieties of rice. We examined the genetic distance among Korean rice varieties using allele frequencies and a genetic diversity analysis with Simple Sequence Repeats (SSRs) markers. The analysis of the genetic diversity and genetic relationships of 243 Korean rice varieties was varied out using 20 SSRs markers. A total of 268 alleles were detected, ranging from 6 to 32, with an average of 13.45 alleles per locus, and and average of gene diversity (GD) of 0.556. Seven SSR markers were selected as key markers for discrimination among the Korean rice varieties. Concerning the results, 243 varieties (100%) were discriminated among by using acrylamide gel and fragment analyzer-based markers. In conclusion, this study provides useful basic data that can be utilized concerning Korean rice varieties breeding and development. In addition, we will have to manage and conserve as a valuable genetic resource, without losing the diversity of Korean rice varieties.

• Plant Resources
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• v.7 no.2
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• pp.93-103
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• 2004

Genetic background and phylogenetic relationships among 20 Korean wheat cultivars were assessed using microsatellites after amplifying with 13 SSR primer pairs. Average allele number per primer pair was 3.36. Genetic similarities for every pair of cultivars ranged from 0.42 to 0.97, with 0.69 of overall average. Korean cultivars were divided into two major groups based on microsatellite DNA polymorphisms. Group I consisted of relatively old cultivars developed until 1970s, and group II contained the recent cultivars developed during 1980s and 1990s. Amongst old elite cultivars/lines, ‘Yukseung 3’, ‘Norin 12’ and ‘Norin 72’ contributed most to the genetic background of cultivars belonging to group I, and ‘Norin 4’, ‘Norin 12’, ‘Norin 43’ and ‘Norin 72’ to group II, respectively. The phylogenetic relationship of Korean wheat cultivars was in accordance with the genealogical data of each cultivar. The genetic background of each cultivar was assessed from the point of breeding and germplasm management such as variety identification and duplicated accessions for assisting in developing a system for the registration of new variety based on the molecular characterization in future.

• International Journal of Industrial Entomology and Biomaterials
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• v.29 no.2
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• pp.169-178
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• 2014

In this study, we investigated genetic diversity of 22 microsporidian isolates infecting tropical tasar silkworm, Antheraea mylitta collected from various geographical forest locations in the state of Jharkhand, India, using polymerase chain reaction (PCR)-based marker assay: random amplified polymorphic DNA (RAPD). A type species, NIK-1s_mys was used as control for comparison. The shape of mature microsporidians was found to be oval to elongate, measuring 3.80 to $5.10{\mu}m$ in length and 2.56 to $3.30{\mu}m$ in width. Of the 20 RAPD primers screened, 16 primers generated reproducible profiles with 298 polymorphic fragments displaying high degree of polymorphism (97%). A total of 14 RAPD primers produced 45 unique putative genetic markers, which were used to differentiate the microsporidians. Calculation of genetic distance coefficients based on dice coefficient method and clustering with un-weighted pair group method using arithmetic average (UPGMA) analysis was conducted to unravel the genetic diversity of microsporidians infecting tasar silkworm. The similarity coefficients varied from 0.059 to 0.980. UPGMA analysis generated a dendrogram with four microsporidian groups, which appear to be different from each other as well as from NIK-1s_mys. Two-dimensional distribution based on Euclidean distance matrix also revealed considerable variability among different microsporidians identified from the tasar silkworms. Clustering of few microsporidian isolates was in accordance with the geographic origin. The results indicate that the RAPD profiles and specific/unique genetic markers can be used for differentiating as well as to identify different microsporidians with considerable accuracy.

• Korean Journal of Medicinal Crop Science
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• v.18 no.2
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• pp.86-92
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• 2010

The polymorphism and the genetic relationships among 32 genetic resources of genus Nelumbo from Korea, Japan, China, USA, India, Thailand and Gabong were thoroughly investigated and extensively examined using ISSR markers. Out of 103 loci detected overall, 94 were identified to be polymorphic with a rate of 91.2%. The genetic similarity matrix revealed a wide range of variability among the 32 accessions, spanning from 0.227 to 0.833. The study findings indicate that the Nelumbo accessions have a high genetic diversity, and accordingly carry a germplasm qualifying as good genetic resources for cross breeding. According to the clustering analysis, different subspecies, N. nucifera and N. lutea, were divided into independent groups and all of the N. nucifera accessions could be classified into five categories. Compared to RAPD analysis, ISSR method showed a clearer picture of polymorphism among the accessions and exhibited a definite distinction even among the subspecies. In this respect, ISSR analysis is considered to be more effective in differentiating the accessions and subspecies of the genus Nelumbo than RAPD test.

• Animal Bioscience
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• v.34 no.1
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• pp.12-19
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• 2021

Objective: The objectives of the current study were to study the main environmental factors affecting birth weight (BW) and weaning weight (WW), estimate variance components, genetic parameters and genetic trend and to evaluate the variability and relationships among breeding value of BW and WW using principal components analysis (PCA). Methods: A total of 16,370 records were collected from 8,271 buffalo calves. Genetic parameters and breeding values were estimated using a bivariate animal model which includes direct, maternal and permanent maternal effects. These estimates were standardized and used in PCA. Results: The direct heritability estimates were 0.06 and 0.41 for BW and WW, respectively whereas direct maternal heritability values were 0.03 and 0.14, respectively. Proportions of variance due to permanent environmental effects of dam were 0.455 and 0.280 for BW and WW respectively. The genetic correlation between BW and WWs was weak approaching zero, but the maternal correlation was 0.26. The first two principal components (PC1 and PC2) were estimated utilizing the standardized breeding values according to Kaiser method. The total variance explained by the first two PCs was 71.17% in which 45.91% and 25.25% were explained by PC1 and PC2, respectively. The direct breeding values of BW were related to PC2 but those of WW and maternal breeding values of BW and WWs were associated with PC1. Conclusion: The results of genetic parameters and PCA indicate that BW and WWs were not genetically correlated and improving growth traits of Egyptian buffaloes could be achieved using WW without any adverse effect by BW.