• Proceedings of the Korean Society of Crop Science Conference
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• 2022.10a
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• pp.267-267
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• 2022

Glutinous rice is a key grain quality trait occupying an important part during rice processing in most rice growing areas. Amylose content (AC) of rice determine eating quality which is one of the major traits in rice breeding program. In this study, a gene pyramiding approach was used to introduce two dull genes, responsible for low amylose contents, for glutinous rice breeding using marker assisted selection (MAS). Two dull genes were located on chromosome 6 (wx-mq, AC: 12.7 %) and chromosome 10 (du1, AC: 10.3%), respectively. To test whether these two dull genes have an epistatic interaction, we developed an F₂ population by crossing two nearly isogenic lines(NILs) harboring wx-mq and du1. Gene based marker and KASP marker were used to select NILs(NIL-nor, NIL-wxmq, NIL-du1, and NIL-wxmq/du1) from the F2 population. A two-way ANOVA revealed an epistatic interaction between the two genes in the F2 population. The mean of Amylose contents for NIL-nor, NIL-wxwq, NIL-(du1, and NIL-wxmq/du1 were 17.3%, 12.5%, 9.7%, and 7.2%, respectively. This interaction was confirmed by an analysis of NILs indicating that both genes are involved in the same genetic mechanism controlling amylose contents. This result will be useful for rice breeding related to amylose content.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.13-13
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• 2017

By the progress of genome sequencing, infrastructures for marker-assisted breeding (MAB) of rice came to be established. Fine mapping and gene isolation have been conducted using the breeding materials derived from natural variations and artificial mutants. Such genetic analysis by the genome-wide dense markers provided us the knowledge about the many genes controlling important traits. We identified several genes or quantitative trait loci (QTL) for heading date, blast resistance, eating quality, high-temperature stress tolerance, and so on. NILs of each gene controlling heading date contribute to elongate the rice harvest period. Determination of precise gene location of blast resistance gene pi21, allowed us to overcome linkage drag, co-introduction of undesirable eating quality. We could also breed the first practical rice cultivar in Japan with a brown planthopper resistance gene bph11 in the genetic back-ground of an elite cultivar. Discovery of major and minor QTLs for good eating quality allowed us to fine-tune of eating quality according to the rice planting area or usage of rice grain. Many rice cultivars have bred efficiently by MAB for several traits, or by marker-assisted backcross breeding through chromosome segment substitution lines (CSSLs) using genetically diverse accessions. We are also systematically supporting the crop breeding of other sectors by MAB or by providing resources such as CSSLs. It is possible to pyramid many genes for important traits by using MAB, but is still difficult to improve the yielding ability. We are performing a Genomic Selection (GS) for improvement of rice biomass and grain yield. We are also trying to apply the genome editing technology for high yield rice breeding.

• Korean Journal of Breeding Science
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• v.40 no.3
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• pp.215-222
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• 2008

Fifty-two Korean japonica rice cultivars were analyzed for leaf blast resistance and genotyped with 4 STS and 26 SSR markers flanking the specific chromosome sites linked with blast resistance genes. In our analysis of resistance genes in 52 japonica cultivars using STS markers tightly linked to Pib, Pita, Pi5(t) and Pi9(t), the blast nursery reaction of the cultivars possessing the each four major genes were not identical to that of the differential lines. Eight of the 26 SSR markers were associated with resistant phenotypes against the isolates of blast nursery as well as the specific Korean blast isolates, 90-008 (KI-1113), 03-177 (KJ-105). These markers were linked to Pit, Pish, Pib, Pi5(t), Piz, Pia, Pik, Pi18, Pita and Pi25(t) resistance gene loci. Three of the eight SSR markers, MRG5836, RM224 and RM7102 only showed significantly associated with the phenotypes of blast nursery test for two consecutive years. These three SSR markers also could distinguish between resistant and susceptible japonica cultivars. These results demonstrate the usefulness of marker-assisted selection and genotypic monitoring for blast resistance of rice in blast breeding programs.

• Journal of Animal Science and Technology
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• v.46 no.3
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• pp.301-306
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• 2004

This study was conducted to develop new markers at the region that was related to QTL affecting intramuscular fat and backfat thickness on chromosome 6q28 - 6q32 in pigs. Dozens of repeated sequences were founded using shotgun sequencing of several BAC clones corresponding to that region, of which five new microstellite markers that identified polymorphism were discovered. The mean number of alleles at each locus observed 2.13(KP0290F2), 4.63(KP0248Cll), 7.38(KP1231C91), 2.75(KPI23IC92) and 6.2S(KP1231C93) in 8 breeds(Landrace, Korean native pig, Duroc, Yorkshire, Berkshire, Wuzhishan pig, Xiang pig, Min pig). The average estimated heterozygosity values at each locus varied from 0.2100(KP0290F2) to 0.8304(KPI23IC91) in all populations. In other hand, the average allele of all loci WlL'I within range of 0.4517(Berkshire) and 0.6957 (Yorkshire). Of these markers, KP0248C11, KP1231C91 and KP1231C93 were identified to have optimal number of alleles, high heterozygosity values and low standard deviation values. Especially, KPI23IC91 and KPI231C93 might be considered as a useful marker for genetic mapping and diversity study.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.8
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• pp.1086-1092
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• 2017

Objective: O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) catalyzes the addition of O-GlcNAc and GlcNAcylation has extensive crosstalk with phosphorylation to regulate signaling and transcription. Pig OGT is located near the region of chromosome X that affects follicle stimulating hormone level and testes size. The objective of this study was to find the variations of OGT between European and Chinese pigs. Methods: Pigs were tested initially for polymorphism in OGT among European and Chinese pigs by polymerase chain reaction and sequencing at the U.S. Meat Animal Research Center (USMARC). The polymorphism was also determined in an independent population of pigs including European and Chinese Meishan (ME) breeds at the National Institute of Animal Science (NIAS, RDA, Korea). Results: The intron 20 of OGT from European and Chinese pigs was 514 and 233 bp, respectively, in the pigs tested initially. They included 1 White composite (WC) boar and 7 sows ($2Minzu{\times}WC$, $2Duroc\;[DU]{\times}WC$, $2ME{\times}WC$, $1Fengzing{\times}WC$) at USMARC. The 281-bp difference was due to an inserted 276-bp element and GACTT in European pigs. When additional WC and ME boars, the grandparents that were used to generate the $1/2ME{\times}1/2WC$ parents, and the 84 boars of 16 litters from mating of $1/2ME{\times}1/2WC$ parents were analyzed, the breeds of origin of X chromosome quantitative trait locus (QTL) were confirmed. The polymorphism was determined in an independent population of pigs including DU, Landrace, Yorkshire, and ME breeds at NIAS. OGT was placed at position 67 cM on the chromosome X of the USMARC swine linkage map. Conclusion: There was complete concordance with the insertion in European pigs at USMARC and NIAS. This polymorphism could be a useful marker to identify the breed of origin of X chromosome QTL in pigs produced by crossbreeding Chinese and European pigs.

• Journal of Chest Surgery
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• v.30 no.7
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• pp.701-707
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• 1997

Although many reseraches have been persued to detect the molecular tumor marker to define the cancer, ideal tumor marker which speak for the characteristics of malignancy and has high sensitivity and specificity is not known. One of the characteristics of the malignant cells is indefinite proliferative potential, in other word, immortality. The expression of telomerase and stabilization of te10meres are con omitant with the attaiunent of immortality in tumor cells; thus the measurement of telomerase activity in clinically obtained tumor samples may provide important information which would be useful as a diagnostic marker to detect immortal cancer cells. Telomerase activity was analyzed in 12 non-small cell . lung cancer cell lines and 41 primary non-small cell lung cancers with the use of a PCR-based assay. All the cell lines and the majority of tumors displayed telomerase activity, but telomerase was not detectable in most of the corresponding pathologically-normal tissues. Telomere length was not correlated with telomerase activity. The present study indicate that measurement of telomerase activity may be useful as a molecular tumor marker in non-small cell lung cancer.

• Molecules and Cells
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• v.27 no.1
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• pp.21-37
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• 2009

Map-based cloning to find genes of interest, marker-assisted selection (MAS), and marker-assisted breeding (MAB) all require good genetic maps with high reproducible markers. For map construction as well as chromosome assignment, development of single copy PCR-based markers and map integration process are necessary. In this study, the 132 markers (57 STS from BAC-end sequences, 13 STS from RFLP, and 62 SSR) were newly developed as single copy type PCR-based markers. They were used together with 1830 markers previously developed in our lab to construct an integrated map with the Joinmap 3.0 program. This integrated map contained 169 SSR, 354 RFLP, 23 STS from BAC-end sequences, 6 STS from RFLP, 152 AFLP, 51 WRKY, and 99 rRAMP markers on 12 chromosomes. The integrated map contained four genetic maps of two interspecific (Capsicum annuum 'TF68' and C. chinense 'Habanero') and two intraspecific (C. annuum 'CM334' and C. annuum 'Chilsungcho') populations of peppers. This constructed integrated map consisted of 805 markers (map distance of 1858 cM) in interspecific populations and 745 markers (map distance of 1892 cM) in intraspecific populations. The used pepper STS were first developed from end sequences of BAC clones from Capsicum annuum 'CM334'. This integrated map will provide useful information for construction of future pepper genetic maps and for assignment of linkage groups to pepper chromosomes.

• The Plant Pathology Journal
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• v.26 no.1
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• pp.70-79
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• 2010

Rice blast is one of the serious devastating diseases. This study was carried out to determine the genetic diversities of blast resistance (R) genes form 86 accessions of aromatic rice with eight SNP markers, z4792, zt4792, z60510, zt6057, k6415, k6411, k39575 and t256, which showed the close-set linkage to 6 major genes, Piz, Piz-t, Pik, Pik-m, Pik-p, and Pit. Four accessions of indica type, Mayataung, Yekywin Yinkya Hmwe, Basmati9-93, and Basmati5854, showed the positive amplicons of six major genes. Among 86 accessions, 83 accessions were detected both or one of Piz and Piz-t genes. Seventy three accessions contained the Piz gene with z4792 marker. In addition, 30 and 71 accessions possessed Piz-t gene with zt4792 and zt6057 markers, respectively. Ten accessions showed the positive bands for the Piz-t gene with both zt4792 and zt6057 markers. Only one accession, Khau Nua Keo, was not amplified for both Piz and Piz-t gene. But japonica type, Gerdeh, possessed only Piz gene between Piz and Piz-t. Fifty two accessions showed the three of Pik multiple genes and Pit gene. Four accessions, Iari7447, Daebunhyangdo2, Shiyayuuine, and Basmati 6129 possessed a Pik-p gene. Especially, Pit gene on chromosome 1 was detected with t256 marker in all of 83 accessions, exception of A-2, one accession of japonica type.

• Korean Journal of Organic Agriculture
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• v.12 no.4
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• pp.451-461
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• 2004

In an animals, identification system has been widely used by ear tag with dummy code and blood typing for parernity. Also, genotyping methods were using for useful mean of individual identification for live animals. In the case of genotyping estimation of gene in population of korean native chicken. In this study, we tested for development of genetic markers used it possible to determination of individual identification system. The candidate genetic markers were used already bow 10 of microstalite DNA sequence information in chromosome No. 1 and 14. Result of analysis for genotyping, the number of alleles of those microstatelites DNA was shown minimal 3 to 12 and the heterozygote expression frequency range was shown from 0.617 to 0.862. In our result, effective number of allele for each microsatellites DNA was shown 3~7, and the accuracy of individual identification was shown nearly 100%, when used with 6 genetic marker. This study was about genotyping method for identification used specific genetic marker form microsatellite DNA in the brand marketing of korean native chicken. Our results suggest that genotyping method used specific genetic marker from microsatellite DNA might be very useful for determination of individual identification.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.136-151
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• 1984

The purpose of this study is to find out the linkage relationship of the resistance genes Wbph1 and Wbph2 which are known to be present in the rice cultivar N22 and ARC 10239 respectively, with the genetic markers which are identified as the specific linkage tester. Crosses were made between the resistant parents and the genetic marker stocks and their F$_2$ populations were grown out in the field. The genetic segregations of the marker character were studied and the seeds were harvested individual plant base. These F$_3$ seeds were grown into plant-line base in the greenhouse and their responses to the whitebacked planthopper were tested. Then the linkage relationship between the F$_2$ plant marker character and the F$_3$ resistance responses to the whitebacked planthopper were examined. In the F$_2$ generation of the crosses between the resistant parent N22 and the genetic marker stocks, the genetic markers, such as lg, d-t, g, la, bl and gl, showed the segregation of 3 dominance to 1 recessiveness, and the Bh marker segregated into 9:7 ratio. Another 4 marker genes, such as Cl, gh, Lh and bc, did not show the good fittness to the expected value. In the F$_2$ generation of the crosses between the resistant parent ARC 10239 and the genetic marker stocks, the genetic markers, such as Cl, lg, Pn, g, la, bl and gl, showed the segregation of 3 dominance to 1 recessiveness, and the Bh gene segregation fitted well to the 9:7. The rest 4 genetic markers, such as gh, Lh, nl and be, did not show the good fitness to the expected ratio. The resistance genes Wbphl of N22 and the Wbph2 of ARC 10239 appeared to be single dominant gene each. The Wbphl gene was linked with the marker gene, liguleless (lg) of linkage group II with the recombination value of 36.8%, and with the black hull (Bh) with the value of 35.9%. The Wbph2 gene appeared to be independent of all the markers tested here, such as Cl, lg, Pn, g, Lh, la, nl, bl, bc, gl, Bh, of linkage gtoup I, II, III, IV, VI, VII, VIII, IX, X, XI, and XII respectively. That the Wbph2 linkage relations were not investigated was regarded as the causes that the tested marker genes on the chromosome were located with the resistance gene at the distant loci, and of the phenctypic properties of the marker characters. The Wbph2 linkage relations should be reexamined in the cross combinations of linkage group Ⅶ, Ⅷ, Ⅹ and XII including linkage group V which was not tested in this experiment.