• Journal of Plant Biology
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• v.38 no.4
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• pp.329-336
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• 1995

Raphanus sativus L. var. hortensis f. raphanistroides (wild radish: Brassicaceae), a herbaceous perennial, occurs only on beaches in East Asia. Genetic diversity and population structure of seven Korean populations were investigated using starch gel electrophoresis. Although the Korean populatins are small, isolated with patchy distribution, the population maintain a moderate level of genetic diversity; the mean percentage fo polymorphic loci was 51.4%, mean number of alleles per locus was 1.84, and mean expected heterozygosity was 0.116. A combination of animal-outcrossing breeding system, wide geographical distribution, restricted ecological distribution, and a propensity for high fecundity may in part be explanatory factors contributing the moderate level of genetic diversity within populations. An overall excess of homozygotes relative to Hardy-Weinberg expetations (mean FISa=0.116) indicates that consanguineous mating occur within wild radish populations, leading to a family structure within a circumscribed area. Although population of wild radish experience a limited gene flow, only 5% of the total genetic variation found in Korean wild radish populations examined is due to differences among populations (mean GST=0.052). This value is considerably lower than the mean values of species with similar life history and ecological characteristics. However, significant differences were found in allele frequencies between populations for all polymorphic loci (P<0.01). It is supposed that directional selection toward genetic uniformity (similar gene frequencies) in a relatively homogenous habitat is thought to be operated among Korean wild radish populations.

• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.220-220
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• 2022

Disproportionating Enzyme 1 (DPE1) is an a-1,4-D-glucanotransferase that cleavages the a-1,4-glucosidic bonds and transfers glucosyl groups. In rice endosperm, it participates in starch synthesis by transferring maltooligosyl groups from amylose and amylopectin to amylopectin. Here, we investigated the haplotype variations and evolutionary indices (e.g., genetic diversity and population structure) for the DPE1 gene in 374 rice accessions representing seven subgroups (wild, indica, temperate japonica, tropical japonica, aus, aromatic, and admixture). Variant calling analysis of DPE1 coding regions leads to the identification of six functional haplotypes representing/occupying 8 nonsynonymous SNPs. Nucleotide diversity analysis revealed the highest pi-value in wild group (0.0556) compared to other cultivated groups, of which temperate japonica showed the most reduction of genetic diversity value (0.003). A significant positive Tajima's D value (1.6330) of admixture highlights sudden population contraction under balancing selection, while temperate japonica with the lowest Tajima's D value (-1.3523) showed a selection signature of DPE1 domestication which might be the cause of excess of rare alleles. Moreover, these two subpopulations exhibits a greater differentiation (F_ST=0.0148), indicating a higher genetic diversity. Our findings on functional DPE1 haplotypes will be useful in future breeding programs, and the evolutionary indices can also be applicable in functional studies of the DPE1 gene.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.2
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• pp.183-188
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• 2012

To investigate the influence of the prolactin receptor 3 (PRLR3) gene and the retinol-binding protein 4 (RBP4) gene on the production traits of swine, genotyping was performed on 156 and 141 Berkshire pigs, respectively, that were carefully selected for economic traits. The frequencies of allele A in the PRLR3 locus and allele B in the RBP4 locus were 0.50 and 0.42, respectively. Neither locus was in the Hardy-Weinberg equilibrium. After a genotype was assigned to the individuals whose parents had the homozygous genotype, a statistical analysis was conducted for 291 pigs. The animals with the PRLR3 and RBP4 genotypes included 182 and 227 head, respectively. Even though the genotypic effects of PRLR3 (p<0.05) and RBP4 (p<0.01) had a significant influence on the pigs' back fat thickness, the interaction of both genes was not highly significant in terms of the back fat thickness (p = 0.1235). While the estimated epistasis effects of aaBB and aaBb decreased the back fat thickness and reduced the growth rate, the effects of AAbb and aabb increased the growth rate. Despite the insignificant difference in the PRLR genotypes in terms of the days to 90 kg and the average daily gain, the back fat thickness showed a significant difference (p<0.05), and the additive effect of allele A and the dominant effect of the hetero-genotype were -0.377 and 1.206 mm, respectively. The RBP4 genotypes had a very significant effect (p<0.01) on the back fat thickness, the days to 90 kg, and the average daily gain. The additive effects of allele B of the RBP4 locus on the back fat thickness, the days to 90 kg, and the average daily gain were 0.70 mm, -1.3 days and 6.2 g, respectively. Moreover, the dominant effects of the heterozygote for those traits were 0.63 mm, 9.9 days and -45.0 g, respectively. Allele A of the PRLR3 locus favorably influenced the back fat thickness, the days to 90 kg of the body weight, and the average daily gain and its dominant effect unfavorably influenced those traits. Allele B of RBP4 showed an incremental growth rate and back fat thickness, which could lower the lean meat percentage in the carcass. The RBP4 hetero-genotype negatively affected the pork production. These results strongly imply that the selection of allele A of PRLR3 and allele B of RBP4 would produce highly productive pigs in the Berkshire breed. Careful selection of allele B of RBP4 is required because of the increase in the back fat thickness.

• Genomics & Informatics
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• v.13 no.4
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• pp.137-145
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• 2015

Selective sweep can cause genetic differentiation across populations, which allows for the identification of possible causative regions/genes underlying important traits. The pig has experienced a long history of allele frequency changes through artificial selection in the domestication process. We obtained an average of 329,482,871 sequence reads for 24 pigs from three pig breeds: Yorkshire (n = 5), Landrace (n = 13), and Duroc (n = 6). An average read depth of 11.7 was obtained using whole-genome resequencing on an Illumina HiSeq2000 platform. In this study, cross-population extended haplotype homozygosity and cross-population composite likelihood ratio tests were implemented to detect genes experiencing positive selection for the genome-wide resequencing data generated from three commercial pig breeds. In our results, 26, 7, and 14 genes from Yorkshire, Landrace, and Duroc, respectively were detected by two kinds of statistical tests. Significant evidence for positive selection was identified on genes ST6GALNAC2 and EPHX1 in Yorkshire, PARK2 in Landrace, and BMP6, SLA-DQA1, and PRKG1 in Duroc. These genes are reportedly relevant to lactation, reproduction, meat quality, and growth traits. To understand how these single nucleotide polymorphisms (SNPs) related positive selection affect protein function, we analyzed the effect of non-synonymous SNPs. Three SNPs (rs324509622, rs80931851, and rs80937718) in the SLA-DQA1 gene were significant in the enrichment tests, indicating strong evidence for positive selection in Duroc. Our analyses identified genes under positive selection for lactation, reproduction, and meat-quality and growth traits in Yorkshire, Landrace, and Duroc, respectively.

• Plant Resources
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• v.6 no.2
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• pp.120-128
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• 2003

The objectives of this study, an analysis of the variation for leaf and fruit characteristics among the selected ten populations of Sorbus commixta Hedl. could be used for the conservation of gene resources and could provide information to superior trees selection. The results obtained from this study can be summarized as follows; Approximately, the Mt. Sungin population at Ulleung island showed larger values in overall characteristics and populations. On the other hand, Mt. Halla population at Jeju island showed the smaller values of the overall characteristics and populations. ANOV A tests showed that there were statistically significant differences in all leaf characteristics among the populations as well as individual trees within populations. But, for fruit characteristics, differences were statistically significant only among the populations. Cluster analysis using single linkage method based on leaf and fruit characteristics showed that ten selected populations of S. commixta in Korea could be clustered into three groups. Group I is Mt. Sungin at Ulleung island, Group II is Mt. Halla at Jeju island, and Group III comprises Osan, Mt. Kaji, Mt. Duckyoo, Mt. Balwang, Mt. Sobaek, Mt. O-dae, Mt. Jiri, and Mt. Taebaek. The selection level based on major agronomic traits, which are the Number of Fruit per Fruiting Lateral(NFL) over 50, and Fruit Length(FL) and Width(FW) over 10 mm, and Weight of 100 Fruit(WFI00) over 66 g, was applied on 100 sample trees, and five trees were selected. The selection effects from selected trees in NFL, FL, FW, and WF100 were evaluated as 132%, 151 %, 142%, and 264% compared to the mean of those 100 sample trees, respectively. Especially, Ulleung 2 showed excellent values that NFL and WFI00 were 95, and 69 g, respectively, suggesting a promising new cultivar for larger fruit and high productivity.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.9
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• pp.1221-1225
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• 2005

The peroxisome proliferator-activated receptors (PPARs) are members of a superfamily of nuclear hormone receptors. Lots of studies in rodents and humans have shown that PPARs were involved in lipid metabolism and adipocyte differentiation. The main objective of this work was to detect the single nucleotide polymorphisms (SNPs) in whole coding regions of peroxisome proliferator-activated receptor alpha (PPAR-$\alpha$) and gamma (PPAR-$\gamma$) genes with approach of single strand conformation polymorphism (SSCP) in the chicken population of Arber Acres broiler, Hyline layer and three Chinese native breeds (Shiqiza, Beijing You, Bai'r). Two SNPs of C1029T and C297T were found in chicken PPAR-$\alpha$ and PPAR-$\gamma$ genes respectively and each SNP found three genotypes in the experimental populations. The results showed that the distribution frequency of 3 genotypes in Arber Acres broiler, Hyline layer and Chinese native breeds had significant differences on the PPAR-$\alpha$ and PPAR-$\gamma$ gene respectively (p<0.01). Furthermore, in the PPAR-$\alpha$ gene, the results of least square estimation for genotypes and body composition traits showed the BB genotype birds had higher abdominal fat weight (AFW) and percentage of abdominal fat (AFP) than AA genotype birds (p<0.05). From these we conjecture the PPAR-$\alpha$ and PPAR-$\gamma$ genes were suffered intensive selection during the long term commercial breeding and the PPAR-$\alpha$ gene may be a major gene or linked to the major genes that impact chicken fat metabolism and the SNPs could be used in molecular assistant selection (MAS) as a genetic marker for the chicken fatness traits.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.11
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• pp.1525-1531
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• 2015

Using next-generation sequencing, we conducted a genome-wide scan of selective sweeps associated with selection toward genetic improvement in Thoroughbreds. We investigated potential phenotypic consequence of putative candidate loci by candidate gene association mapping for the finishing time in 240 Thoroughbred horses. We found a significant association with the trait for Ral GApase alpha 2 (RALGAP2) that regulates a variety of cellular processes of signal trafficking. Neighboring genes around RALGAP2 included insulinoma-associated 1 (INSM1), pallid (PLDN), and Ras and Rab interactor 2 (RIN2) genes have similar roles in signal trafficking, suggesting that a co-evolving gene cluster located on the chromosome 22 is under strong artificial selection in racehorses.

• Proceedings of the Korean Statistical Society Conference
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• 2005.05a
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• pp.17-23
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• 2005

In this paper we consider the well-known semiparametric proportional hazards models for survival analysis. These models are usually used with few covariates and many observations (subjects). But, for a typical setting of gene expression data from DNA microarray, we need to consider the case where the number of covariates p exceeds the number of samples n. For a given vector of response values which are times to event (death or censored times) and p gene expressions(covariates), we address the issue of how to reduce the dimension by selecting the significant genes. This approach enables us to estimate the survival curve when n ${\ll}$p. In our approach, rather than fixing the number of selected genes, we will assign a prior distribution to this number. The approach creates additional flexibility by allowing the imposition of constraints, such as bounding the dimension via a prior, which in effect works as a penalty To implement our methodology, we use a Markov Chain Monte Carlo (MCMC) method. We demonstrate the use of the methodology to diffuse large B-cell lymphoma (DLBCL) complementary DNA (cDNA) data and Breast Carcinomas data.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.8
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• pp.1065-1070
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• 2006

The avian uncoupling protein (avUCP) is a member of the mitochondrial transporter superfamily that uncouples proton entry in the mitochondrial matrix from ATP synthesis. The sequencing analysis method was used to identify nucleotide polymorphisms within the avUCP gene in Korean native chicken (KNC). This study identified ten single nucleotide polymorphisms (SNPs) in the avUCP gene. We analyzed the SNPs of the avUCP gene to investigate whether polymorphism in the gene might be responsible for quantitative variations in economic traits in KNC. Three significant polymorphic sites for economic traits were avUCP C+282T (mean body weight, p<0.05), avUCP C+433T (daily percent lay, p<0.05), and avUCP T+1316C (daily percent lay, p<0.05). The frequency of each SNP was 0.125 (C+282T in avUCP gene exon 1 region), 0.150 (C+433T in avUCP gene intron 1 region), and 0.15 (T+1316C in avUCP gene exon 3 region), respectively. Among the identified SNPs, one pair of SNPs (genotype CC, C+282T and TT, avUCP C+433T) showed the highest daily percent lay (p<0.05) and mean body weight (p<0.05) and the frequency was 0.067. This study of the avUCP gene could be useful for genetic studies of this gene and selection on economic traits for KNC.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.11
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• pp.1555-1559
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• 2003

The objective of the present study was to explore associations between five microsatellites linked to $Fec^B$ and $FecX^I$ genes and litter size in Small Tail Han sheep. The polymorphisms of five microsatellite loci, OarAE101, BM1329, BMS2508, TGLA54 and TGLA68 were detected in 244 ewes of Small Tail Han sheep. Analysis of association between three microsatellite loci (BMS2508, BM1329 and OarAE101) located in the 10 cM region covering the $Fec^B$ gene (Booroola gene) and litter size in Small Tail Han sheep indicated that BMS2508 had significant effect on litter size in the second parity (p<0.05), but no significant effect on litter size in the first parity (p>0.05), while the other two microsatellite loci had no significant effect on litter size in both the first and the second parity in Small Tail Han sheep (p>0.05). At microsatellite locus BMS2508, least squares means in the second parity of genotypes 101/111 and 99/109 were significantly higher than those of genotypes 99/99, 99/101, 99/111 and 99/115 (p<0.05); least squares mean in the second parity of genotype 101/111 was significantly higher than that of genotypes 109/111 and 111/111 (p<0.05). Results of this study also indicated that two microsatellite loci (TGLA54 and TGLA68) that confined the 28.7 cM region covering the $FecX^I$ gene (Inverdale gene) did not affect litter size in both the first and the second parity in Small Tail Han sheep significantly (p>0.05). The information found in the present study is very important for improving the reproductive performance in sheep breeds by marker assisted selection.