• Korean Journal of Breeding Science
• /
• v.50 no.4
• /
• pp.424-433
• /
• 2018

Watermelon (Citrullus lanatus) is an economically important vegetable crop all over the world, which has functional compounds such as lycopene and citrulline. Gummy stem blight caused by Didymella bryoniae is one of the most devastative diseases in watermelon. Single nucleotide polymorphisms (SNPs), which are genetic variations occurring between individuals with respect to a single base, were often used to construct genetic linkage maps and develop molecular markers linked to a variety of horticultural traits and resistance to several diseases. In this study, we developed high-resolution melting (HRM) markers based on SNPs generated from NGS resequencing of two parents in watermelon. Plant materials were C. lanatus '920533' (female and susceptible parent), C. amarus 'PI 189225' (male and resistant parent), and their $F_1$ and $F_2$ progenies. A total of 13.6 Gbp ('920533') and 13.1 Gbp ('PI 189225') of genomic sequences were obtained using NGS analysis. A total of 6.09 million SNPs between '920533' and 'PI 189225' were detected, and 354,860 SNPs were identified as potential HRM primer sets. From these, a total of 330 primer sets for HRM analysis were designed. As a result, a total of 61 HRM markers that have polymorphic melting curves were developed. These HRM markers can be used for the construction of SNP-based linkage maps and for the analysis of quantitative trait loci (QTLs) related to gummy stem blight resistance.

• Journal of Ginseng Research
• /
• v.38 no.2
• /
• pp.130-135
• /
• 2014

Background: Panax ginseng, the most famous medicinal herb, has a highly duplicated genome structure. However, the genome duplication of P. ginseng has not been characterized at the sequence level. Multiple band patterns have been consistently observed during the development of DNA markers using unique sequences in P. ginseng. Methods: We compared the sequences of multiple bands derived from unique expressed sequence tagsimple sequence repeat (EST-SSR) markers to investigate the sequence level genome duplication. Results: Reamplification and sequencing of the individual bands revealed that, for each marker, two bands around the expected size were genuine amplicons derived from two paralogous loci. In each case, one of the two bands was polymorphic, showing different allelic forms among nine ginseng cultivars, whereas the other band was usually monomorphic. Sequences derived from the two loci showed a high similarity, including the same primer-binding site, but each locus could be distinguished based on SSR number variations and additional single nucleotide polymorphisms (SNPs) or InDels. A locus-specific marker designed from the SNP site between the paralogous loci produced a single band that also showed clear polymorphism among ginseng cultivars. Conclusion: Our data imply that the recent genome duplication has resulted in two highly similar paralogous regions in the ginseng genome. The two paralogous sequences could be differentiated by large SSR number variations and one or two additional SNPs or InDels in every 100 bp of genic region, which can serve as a reliable identifier for each locus.

• Journal of Korean Society of Forest Science
• /
• v.105 no.3
• /
• pp.309-314
• /
• 2016

A locally adapted plant population under harsh environmental changes might survive for a long generation through maintaining proper level of genetic diversity. When it happens losing the genetic diversity too much fast, the population could be declining and probably become extinct. An isolated small population of Populus davidiana was investigated to study out the genetic diversity and the fine-scale spatial genetic structure. The estimated number of adult trees in the population of Mt. Worak, South Korea, was 350 in the total area of $14,000m^2$. The number of adults in a study plot ($70m{\times}70m$) was 123. The average age was 16-year-old and a 32-year-old tree was the oldest. The distribution of individuals was slightly aggregated in the plot. Sixty-one among the 123 individuals were randomly sampled to estimate genetic variation using AFLP markers. One hundred fifty-one (77%) of total 196 amplicons were polymorphic from six AFLP primer combinations. The average number of loci per primer combination was 32.7 (S.D.=7.2). Expected heterozygosity ($H_e$) and Shannon's diversity index (S.I.) were 0.154 and 0.254, respectively. These values were extremely lower than those of other P. davidiana populations in South Korea. Genetic patchiness was showed within 21 meters by spatial autocorrelation analysis and the isolated small size of population might be mainly attributed to the formation of such small patch size.

• Horticultural Science & Technology
• /
• v.31 no.3
• /
• pp.344-351
• /
• 2013

Microsatellite is one of the most suitable marker for cultivar identification as it has great discrimination power for cultivars with narrow genetic variation. The polymorphism level between 358 microsatellite primer pairs and 11 commercial cucumber cultivars was investigated. Thirty-one primer pairs showed high polymorphism within cucumber cultivars with different fruit types. These markers were applied for the constructing DNA profile data base of 110 commercial cucumber cultivars through multiplex PCR and fluorescence based automatic detection system. A total of 139 polymorphic amplified fragments were obtained by using 31 microsatellite markers. The average of PIC value was 0.610 ranging from 0.253 to 0.873. One hundred and thirty nine microsatellite loci were used to calculate Jaccard's distance coefficients for UPGMA cluster analysis. A clustering group of varieties, based on the results of microsatellite analysis, were categorized into plant shape and fruit type. Almost the cultivars were discriminated by marker genotypes. This information may be useful to compare through genetic relationship analysis between existing variety and candidate varieties in distinctive tests and protection of plant breeders' intellectual property rights through variety identification.

• Journal of Animal Science and Technology
• /
• v.50 no.6
• /
• pp.733-740
• /
• 2008

The purpose of this study was to assess the genetic variation and establish the relationship amongst Hanwoo, Angus and Holstein breed. The genetic characteristics and variability within Hanwoo(300), Angus(80) and Holstein(50) were estimated on the basis of relationships determined using the 10 kinds of microsatellite, which is located on different chromosomes. Frequencies of microsatellites markers were used to estimate heterozygosities, polymorphic information content(PIC) and genetic distances. The PICs ranged from 0.604 to 0.872(Hanwoo), from 0.562 to 0.812(Angus) and from 0.471 to 0.828(Holstein). Observed heterozygosity and PIC of Hanwoo are the highest among the analyzed breeds. Additionally, Estimates of genetic distance can be utilized to identify genetic relationships between Hanwoo and the other breed. Genetic distances(0.233) between Hanwoo and Angus was lower than distances between Hanwoo and Holstein(2.283). Also, Genetic distances between Angus and Holstein was shown for(2,400). The other side, each individuals were not ramified to different group and were spread evenly in phylogenetic dendrogram about all the populations.

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.9
• /
• pp.1184-1191
• /
• 2011

We attempted to generate a linkage map using Illumina Porcine 60K SNP Beadchip genotypes of the $F_2$ offspring from Korean native pig (KNP) crossed with Yorkshire (YS) pig, and to identify quantitative trait loci (QTL) using the line-cross model. Among the genotype information of the 62,136 SNPs obtained from the high-density SNP analysis, 45,308 SNPs were used to select informative markers with allelic frequencies >0.7 between the KNP (n = 16) and YS (n = 8) F0 animals. Of the selected SNP markers, a final set of 500 SNPs with polymorphic information contents (PIC) values of >0.300 in the $F_2$ groups (n = 252) was used for detection of thirty meat quality-related QTL on chromosomes at the 5% significance level and 10 QTL at the 1% significance level. The QTL for crude protein were detected on SSC2, SSC3, SSC6, SSC9 and SSC12; for intramuscular fat and marbling on SSC2, SSC8, SSC12, SSC14 and SSC18; meat color measurements on SSC1, SSC3, SSC4, SSC5, SSC6, SSC10, SSC11, SSC12, SSC16 and SSC18; water content related measurements in pork were detected on SSC4, SSC6, SSC7, SSC10, SSC12 and SSC14. Additional QTL of pork quality traits such as texture, tenderness and pH were detected on SSC6, SSC12, SSC13 and SSC16. The most important chromosomal region of superior pork quality in KNP compared to YS was identified on SSC12. Our results demonstrated that a QTL linkage map of the $F_2$ design in the pig breed can be generated with a selected data set of high density SNP genotypes. The QTL regions detected in this study will provide useful information for identifying genetic factors related to better pork quality in KNP.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.56 no.4
• /
• pp.322-328
• /
• 2011

AFLP markers were employed to detect genetic diversity and genetic relationship among 26 accessions of foxtail millet collected from Korea. Analysis of 26 accessions of foxtail millet with nine AFLP primer set combinations detected a total of 170 bands, of which 145 (85.3%) showed polymorphic at the species level. The phenotypic diversity (Hs) calculated for the nine primer combinations ranged from 1.84 to 6.8, with an average of 3.85. The average phenotypic diversity values were 3.39 and 2.99 for accessions collected from Gangwon province (Group 1), and accessions collected from the other areas including Gyeonggi province (Group 2), respectively. In the cluster analysis of 26 accessions, two major groups were recognized at 73% genetic similarity. Group I includes 13 accessions, which were collected in Gangwon province, and 1 accession, which was collected in Gyeonggi province, with genetic similarity of 76.8%. Group II includes two accessions, which were collected in Gangwon province, and 10 accessions, which were collected in the other areas with genetic similarity of 78.9%. The presenting data on the assessment of genetic diversity and genetic relationships among Korean accessions of foxtail millet will be helpful for efficient collection or conservation strategy of foxtail millet germplasm in Korea.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.6
• /
• pp.2629-2633
• /
• 2012

Background: Raw betel nut (RBN) chewing is an important contributing factor for esophageal squamous cell carcinoma (ESCC), although associated genomic changes remain unclear. One difficulty in assessing the effects of exclusively RBN induced genetic alterations has been that earlier studies were performed with samples of patients commonly using tobacco and alcohol, in addition to betel-quid. Both CDKN2A (at 9p21) and Rb1 gene (at 13q14.2) are regarded as tumor suppressors involved in the development of ESCC. Therefore, the present study aimed to verify the RBN's ability to induce ESCC and assess the involvement of CDKN2A and Rb1 genes. Methods: A panel of dinucelotide polymorphic markers were chosen for loss of heterozygosity studies in 93 samples of which 34 were collected from patients with only RBN-chewing habit. Promoter hypermethylation was also investigated. Results: Loss in microsatellite markers D9S1748 and D9S1749, located close to exon $1{\beta}$ of CDKN2A/ARF gene at 9p21, was noted in 40% ESCC samples with the habit of RBN-chewing alone. Involvement of a novel site in the 9p23 region was also observed. Promoter hypermethylation of CDKN2A gene in the samples with the habit of only RBN-chewing alone was significantly higher (p=0.01) than Rb1 gene, also from the samples having the habit of use both RBN and tobacco (p=0.047). Conclusions: The data indicate that the disruption of 9p21 where CDKN2A gene resides, is the most frequent critical genetic event in RBN-associated carcinogenesis. The involvement of 9p23 as well as 13q14.2 could be required in later stages in RBN-mediated carcinogenesis.

• Journal of Life Science
• /
• v.18 no.9
• /
• pp.1225-1229
• /
• 2008

A total of 10 polymorphic microsatellite markers on bovine chromosome 5 were used for allelic association tests with phenotypic characteristics in Hanwoo. The data analyzed in this study were collected from 326 steers. Chi-square tests were performed to compare the frequencies of individual alleles between the high and the low breeding value groups. The following breeding values were analyzed for QTL effects. The frequency of allele 239 of DIK2828 showed a significant difference between the high and the low breeding value groups in the breeding value of marbling score (MSBV). The allele 279 of BMC1009 was found to show significant differences in allelic distribution for the breeding value of cold carcass weight (CWBV) and the breeding value of backfat thickness (BFBV) and allele 285 showed significant differences in allelic distribution for CWBV, BFBV, and MSBV. The allele 200 of DIK4329 showed significant differences in allelic distributions for the breeding values of longissimus muscle area (LMABV) and BFBV. In this study, we identified the QTL for carcass traits at around 20 (DIK2828), 41 (BMC1009) and 95 (DIK4329) cM in chromosome 5. The results provided a useful reference for further positional candidate gene research and marker-assisted selection for fat metabolism and carcass traits.

• Korean Journal of Plant Taxonomy
• /
• v.32 no.4
• /
• pp.383-396
• /
• 2002

RAPD analyses were compared for 17 taxa of Korean Iris including the subgenus Sisyrinchium and Belamcanda. Eighty scorable RAPD markers were formed from the PCR reactions using 10 random oligoprimers. In this systematic analyses which used neighbor-joining methods including bootstrapping analyses with genetic coefficients, the Korean Iris were divided into three subgenera (Limniris, Crossiris, Pardanthopsis), or two genera (Limniris, Pardanthopsis). The molecular data agree with the previous classification system that recognized two sections and six series for the subgenus Limniris because the subgenus is comprised of four clades in the RAPD analyses. According to the molecula data, the series Chinensis should be divided into two groups. The minutoaurea group is composed of I. koreana, I. odaesanensis, and I. minitoaurea, while the rossi group is comprised of two varieties of I. rossi. The series Tripetalae is closely allied with the series Sibiricae, whereas the series Ensatae is recognized as a sister group to the series Ruthencae. The molecular phylogeny, which was based on RAPD analysis, for the most part agreed with the data proposed by previous authors. This is because the basis of morphological and ITS sequence data suggests that the RAPD markers should be very useful in addressing phylogenetic questions about the genus Iris.