• Journal of Embryo Transfer
• /
• v.19 no.3
• /
• pp.291-299
• /
• 2004

Characterization of quantitative trait loci (QTL) was investigated in the experimental cross population between Berkshire and Yorkshire breed. A total of 512 F$_2$ offspring from 65 matting of F$_1$ parents were phenotyped the carcass traits included average daily gain (ADG), average backfat thickness (ABF), tenth rip backfat thickness (TRF), loin eye area (LEA), and last rip backfat thickness (LRF). All animals were genotyped for 125 markers across the genome. Marker linkage maps were derived and used in QTL analysis based on line cross least squares regression interval mapping. A decision tree to identify QTL with imprinting effects was developed based on tests against the Mendelian mode of QTL expression. To set the evidence of QTL presence, empirical significance thresholds were derived at chromosome-wise and genome-wise levels using specialized permutation strategies. Significance thresholds derived by the permutation test were validated in the data set based on simulation of a pedigree and data structure similar to the Berkshire-Yorkshire population. Genome scan revealed significant evidences for 13 imprinted QTLs affecting growth and body compositions of which nine were identified to be QTL with paternally expressed inheritance mode. Four of QTLs in the loin eye area (LEA), and tenth rip backfat thickness (TRF), a maternally expressed QTL were found on chromosome 10 and 12. These results support the useful statistical models to analyse the imprinting far the QTLs related carcass trait.

• Journal of Korean Society of Forest Science
• /
• v.87 no.3
• /
• pp.422-428
• /
• 1998

Polymerase chain reaction(PCR)-based inter-simple sequence repeats(I-SSR) markers were analyzed in 48 megagametophytes of a single tree of Abies koreana $W_{ILS}$. Nineteen of the 35 primers, screened with 6 megagametophyte DNA and produced the clearest amplification products in the preliminary experiment, were used for PCR with 48 megagametophyte DNAs sampled from a single tree. On the basis of the chi-square test, a total of 51 amplicons, amplified by the 19 primers, were revealed to be segregated according to the Mendelian ratio(i.e., 1 : 1 segregation ratio) in the 48 megagametophytes at 5% significance level. Based on the linkage analysis, the observed 51 Mendelian loci turned out to be unlinked each other, which suggested that they are evenly distributed in the genome. However, majority of RAPD markers are known to belong to the independent linkage blocks, which frequently results in the amplification of RAPD markers from the restricted regions of the genome. Owing to the nature of even distribution of the 51 loci observed in this study, the I-SSR markers could give better resolution of estimating genetic diversity from the whole genome than RAPD markers. And I-SSR markers are also more suitable than RAPD markers for reconstructing phylogenetic relationship by a cladistic method which requires to fulfil the assumption of independent evolution of the different characters.

• Korean Journal of Plant Resources
• /
• v.17 no.2
• /
• pp.107-115
• /
• 2004

To develop universal primers for phylogenetic analysis and species-specific marker for breeding program of kiwifruit, eighteens primers were designed from kiwifruit genome-specific repeat sequences. Seven species including twenty two varieties collected from native eastern Asia were examined using 18 to 22 mer kiwifruit target(KT) primers. among eighteen primers, we selected seven primers for phylogenetic relationship. The genus Actinidia was divided into two large groups; group I,A. arguta, A. melanandra, A. kolomikta, and A. marcrosperma, characterized by the non-hair in fruits and loaves or a few pubescences only in young stage, which belongs to the section Leiocarpae, and group II, A. chinensis, A. deliciosa, and A. eriantha, characterized by a lot of hairs only in young fruit stage and with a lot of hairs or fuzzes in leaves and branches, which belongs to the section Stellatae. Group II especially belongs to the series Perfectae of the section Stellatae and was divided into two subgroups; subgroup I containing A. chinensis and A. deliciosa, and subgroup II containing A. eriantha. In contrast, the two species, A. chinensis and A. deliciosa, which are known to have common parents, were divided into two independent subgroups with 80％ of a similarity value. On the other hand, we selected KT6F for variety specific bands, KT12E primers for 'Hayward' and 'Tomuri'. KT7F or KT12F primers were useful for analysis of inheritance pattern in kiwifruit cross-breeding. We suggest that these primers will be a powerful tool for elucidating phylogenetic relationship and selection of novelty kiwifruit in a breeding program.

• Korean journal of applied entomology
• /
• v.40 no.4
• /
• pp.337-344
• /
• 2001

The house fly (Musca domestica L.) strains were derived from the Yumenoshima III strain by selecting with cypermethrin and methomyl for 19 and 16 generations, respectively. The resulting strains, cypermethrin resistance strain (Cyp-R19) and methomyl resistance strain (Met-R16), showed high level of resistance by 12906 and 51 times, respectively, comparing with the susceptible SRS strain. The Cyp-R19 strain was resistant to synthetic pyrethroids such as deltamethrin, esfenvalerate, fenpropathrin, $\beta$-cyfluthrin, showing > 11000, 1231, 103, 292 times higher $LD_{50}$ values than the SRS strain, respectively. It was also resistant to 3 organophosphates and 2 carbamates such as fenitrothion, profenofos, pyridaphenthion, benfuracarb, methomyl, showing resistance ratios fo 51, 17, 49, 39 and 62 comparing to SRS strain. The Met-R16 strain was resistant to synthetic carbamate benfuracarb, showing 6 times higher $LD_{50}$ value than SRS strain. It was also resistant to 4 organophosphates such as acephate, fenitrothion, profenofos and pyridaphenthion, showing > 40, 103, 19, 60 times higher $LD_{50}$ value. It was also resistant to 5 pyrethroids and a pyrrole such as cypermethrin, deltamethrin, esfenvalerate, fenpropathrin, $\beta$-cyfluthrin and chlorfenapyr, showing 3030, 249, 4063, 34, 330 and 86 times higher $LD_{50}$ values than the SRS strain. Cyp-R14 strain which was selected for 14 generations by cypermethrin and developed 11014 times higher resistance to the SRS strain was used in the dominance and linkage group analysis. Cypermethrin resistance inheritance was incompletely dominant in house fly as judged by the reciprocal cross between the resistant and susceptible strains. The linkage group analysis for the major factors responsible for this resistance was carried out by the$ F_1$male-backcross method, using susceptible multi-chromosomal marker aabys strain. The major factors for cypermethrin resistance were located on the 1st, the 3rd and the 4th chromosomes, and the effect of the 3rd chromosome was most prominent.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.68 no.3
• /
• pp.134-146
• /
• 2023

Phytophthora root rot (PRR) is a major soybean disease caused by an oomycete, Phytophthora sojae. PRR can be severe in poorly drained fields or wet soils. The disease management primarily relies on resistance genes called Rps (resistance to P. sojae). This study aimed to identify resistance loci associated with resistance to P. sojae isolate 40468 in Daepung × CheonAl recombinant inbred line (RIL) population. CheonAl is resistant to the isolate, while Daepung is generally susceptible. We genotyped the parents and RIL population via high-throughput single nucleotide polymorphism genotyping and constructed a set of genetic maps. The presence or absence of resistance to P. sojae was evaluated via hypocotyl inoculation technique, and phenotypic distribution fit to a ratio of 1:1 (R:S) (χ² = 0.57, p = 0.75), indicating single gene mediated inheritance. Single-marker association and the linkage analysis identified a highly significant genomic region of 55.9~56.4 megabase pairs on chromosome 18 that explained ~98% of phenotypic variance. Many previous studies have reported several Rps genes in this region, and also it contains nine genes that are annotated to code leucine-rich repeat or serine/threonine kinase within the approximate 500 kilobase pairs interval based on the reference genome database. CheonAl is the first domestic soybean genotype characterized for resistance against P. sojae isolate 40468. Therefore, CheonAl could be a valuable genetic source for breeding resistance to P. sojae.

• Journal of Life Science
• /
• v.18 no.12
• /
• pp.1733-1738
• /
• 2008

SLC6A18, one of the neurotransmitters, was reported the possible relationship to hypertension, and it contained eight blocks of minisatellites. In this study, SLC6A18-MS5 sequence which showed the highest heterozygosity among seven minisatellites was analyzed using the Transfac software, the putative binding sites for the transcription factor Pax4 and HNF4 were discovered as a result. The HNF4 is involved in the diabetes pathway and suggested the relationship to hypertension. Thus, we investigated the putative functional significance of allelic variation in this minisatellites with respect to susceptibility for hypertension. To address this possibility, we analyzed genomic DNA from the blood of 301 hypertension-free controls and 184 cases with hypertension. A statistically significant association was not identified between the allelic distribution of SLC6A18-MS5 and occurrence of hypertension. We then examined the meiotic segregation of SLC6A18-MS5 and it was transmitted following Mendelian inheritance. Therefore, this locus could be useful markers for paternity mapping and DNA fingerprinting. Moreover, we undertook a comprehensive analysis of the genomic sequence to address the evolutionary events of these variable repeats. SLC6A18 minisatellites regions are only conserved in human and primates. This result suggestedthat intronic minisatellites analysis is powerful evolution marker for the non-coding regions in primates and can provide a great insight to the molecular evolution of repeated region in primates.