Objective: The present study was to investigate the association of polymorphisms in exon-9 of the bone morphogenetic protein receptor-1B (BMPR-1B) gene (C864T) with litter size in 240 Dorset, 232 Mongolian, and 124 Small Tail Han ewes. Methods: Blood samples were collected from 596 ewes and genomic DNA was extracted using the phenol: chloroform extraction method. The 304-bp amplified polymerase chain reaction product was analyzed for polymorphism by single-strand conformation polymorphism method. The genotypic frequency and allele frequency of BMPR-1B gene exon-9 were computed after sequence alignment. The ${\chi}^2$ independence test was used to analyze the association of genotypic frequency and litter size traits with in each ewe breed, where the phenotype was directly treated as category. Results: The results indicated two different banding patterns AA and AB for this fragment, with the most frequent genotype and allele of AA and A. Calculated Chi-square test for BMPR-1B gene exon-9 was found to be more than that of p value at the 5% level of significance, indicating that the population under study was in Hardy-Weinberg equilibrium for all ewes. The ${\chi}^2$ independence test analyses indicated litter size differences between genotypes was not the same for each breed. The 304-bp nucleotide sequence was subjected to BLAST analysis, and the C864T mutation significantly affected litter size in singletons, twins and multiples. The heterozygosity in exon-9 of BMPR-1B gene could increase litter size for all the studied ewes. Conclusion: Consequently, it appears that the polymorphism BMPR-1B gene exon-9 detected in this study may have potential use in marker assisted selection for litter size in Dorset, Mongolian, and Small Tail Han ewes.
Hwang, Ji Young;Park, Jae Kyun;Kim, Tae Hyung;Eum, Jin Hee;Song, Haengseok;Kim, Jin Young;Park, Han Moie;Park, Chan Woo;Lee, Woo Sik;Lyu, Sang Woo
Clinical and Experimental Reproductive Medicine
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v.47
no.4
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pp.312-318
/
2020
Objective: The objective of the study was to compare the effects of long-term and short-term embryo culture to assess whether there is a correlation between culture duration and clinical outcomes. Methods: Embryos were divided into two study groups depending on whether their post-warming culture period was long-term (20-24 hours) or short-term (2-4 hours). Embryo morphology was analyzed with a time-lapse monitoring device to estimate the appropriate timing and parameters for evaluating embryos with high implantation potency in both groups. Propensity score matching was performed to adjust the confounding factors across groups. The grades of embryos and blastocoels, morphokinetic parameters, implantation rate, and ongoing pregnancy rate were compared. Results: No significant differences were observed in the implantation rate or ongoing pregnancy rate between the two groups (long-term culture group vs. short-term culture group: 56.3% vs. 67.9%, p=0.182; 47.3% vs. 53.6%, p=0.513). After warming, there were more expanded and hatching/hatched blastocysts in the long-term culture group than in the short-term culture group, but there was no significant between-group difference in embryo grade. Regarding pregnancy outcomes, the time to complete blastocyst re-expansion after warming is shorter in women who became pregnant than in those who did not in both culture groups (long-term: 2.19±0.63 vs. 4.11±0.81 hours, p=0.003; short-term: 1.17±0.29 vs. 1.94±0.76 hours, p=0.018, respectively). Conclusion: The outcomes of short-term culture and long-term culture were not significantly different in vitrified-warmed blastocyst transfer. Regardless of the post-warming culture time, the degree of blastocyst re-expansion 3-4 hours after warming is an important marker for embryo selection.
The blood clam, Tegillarca granosa, is economically important in marine bivalve and is used in fisheries industry among western Pacific Ocean Coasts especially in Korea, China, and Japan. The number of chromosomes in the blood clam is known as 2n=38, but the genome size and genetic information of the genome are not still clear. In order to predict the genomic size of the T. granosa, the in-silico analysis analysed the genomic size using short DNA sequence information obtained using the NGS Illumina HiSeq platform. As a result, the genomic size of T. granosa was estimated to be 770.61 Mb. Subsequently, a draft genome assembly was performed through the MaSuRCA assembler, and a simple sequence repeat (SSR) analysis was done by using the QDD pipeline. 43,944 SSRs were detected from the genome of T. granosa and 69.51% di-nucleotide, 16.68% trinucleotide, 12.96% tetra-nucleotide, 0.82% penta-nucleotide, and 0.03% hexa-nucleotide were consisted. 100 primer sets that could be used for genetic diversity studies were selected. In the future, this study will help identify the genetic diversity of T. granosa and population genetic studies, and further identify the classification of origin between homogenous groups.
Seong Seok Choi;Seung Hyun Yoo;Yong Bae Seo;Jong Oh Kim;Ik Jung Kwon;So Hee Bae;Gun Do Kim
Journal of Life Science
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v.33
no.12
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pp.1025-1035
/
2023
In this study, we analyzed SNPs that appear between Korean and Chinese Scapharca subcrenata using the nucleotide sequence data of S. subcrenata analyzed by genotyping by sequencing (GBS). To distinguish the country of origin for S. subcrenata in Korean and Chinese, we developed a primer set as single nucleotide polymorphism (SNP) markers for quantitative real-time PCR (qPCR) analysis and validated by sequencing SNPs. A total of 180 samples of S. subcrenata were analyzed by genotyping by sequencing, and 15 candidate SNPs were selected. SNP marker selection for country of origin were identified through real-time qPCR. Insertion 1 and SNP 21 markers showed the most distinct separation between the sequence types as well as the country of origin through qPCR, with the observed amplification patterns matching the expected outcomes.. Additionally, in a blind test conducted by mixing samples of S. subcrenata at random, Insertion 1 showed 74% accuracy, 52% sensitivity, and 96% specificity, and SNP 21 showed 86% accuracy, 79% sensitivity, and 93% specificity. Therefore, the two SNP markers developed are expected to be useful in verifying the authenticity of the country of origin of S. subcrenata when used independently or in combination.
Kim, Ho Bang;Kim, Jae Joon;Oh, Chang Jae;Yun, Su-Hyun;Song, Kwan Jeong
Journal of Plant Biotechnology
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v.43
no.3
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pp.261-271
/
2016
Citrus is an economically important fruit crop widely growing worldwide. However, citrus production largely depends on natural hybrid selection and bud sport mutation. Unique botanical features including long juvenility, polyembryony, and QTL that controls major agronomic traits can hinder the development of superior variety by conventional breeding. Diverse factors including drastic changes of citrus production environment due to global warming and changes in market trends require systematic molecular breeding program for early selection of elite candidates with target traits, sustainable production of high quality fruits, cultivar diversification, and cost-effective breeding. Since the construction of the first genetic linkage map using isozymes, citrus scientists have constructed linkage maps using various DNA-based markers and developed molecular markers related to biotic and abiotic stresses, polyembryony, fruit coloration, seedlessness, male sterility, acidless, morphology, fruit quality, seed number, yield, early fruit setting traits, and QTL mapping on genetic maps. Genes closely related to CTV resistance and flesh color have been cloned. SSR markers for identifying zygotic and nucellar individuals will contribute to cost-effective breeding. The two high quality citrus reference genomes recently released are being efficiently used for genomics-based molecular breeding such as construction of reference linkage/physical maps and comparative genome mapping. In the near future, the development of DNA molecular markers tightly linked to various agronomic traits and the cloning of useful and/or variant genes will be accelerated through comparative genome analysis using citrus core collection and genome-wide approaches such as genotyping-by-sequencing and genome wide association study.
The objective of this study was carried out to examine the selection effects of in vitro matured porcine follicular oocytes with polar body extrusion and early cleavage as non-invasive marker to know the developmental competence in advance. The porcine oocytes matured for 48 h were examined the polar body extrusion. The examined oocytes were matured for additional $16{\sim}18h$ and activated with 7% ethanol and cultured in $5{\mu}g/ml$ cytochalasin B for 5 h for diploid formation. The treated oocytes were cultured and examined the cleavage after 48 h and continued culturing for 5 days. The oocytes of 21.9% were discarded in morphological selection and 32.1% oocytes were discarded by failure of first polar body extrusion. The selected oocytes were matured and activated and then after 48 h the cleavage rates were examined. In morphologically selected oocytes, 15.8% oocytes were not cleaved and 52.6% oocytes were normally cleaved and 31.6% oocytes were hyper-cleaved over 8-cell stage. However in the first polar body extruded oocytes, 7.1% oocytes were not cleaved and 73.1% oocytes were normally cleaved and 19.8% oocytes were hyper-cleaved. The morphologically selected embryos that not cleavage-selected were developed in 16.7% up to blastocyst and the morphologically selected and cleavage-selected embryos were developed in 31.7%. The polar body extruded oocytes that were not carried out cleavage selection were developed in 39.0% and the polar body extruded and cleavage-selected embryos were developed 49.0%. The first cleavage timing was examined with 12 h interval after activation. In $0{\sim}12,\;12{\sim}24,\;24{\sim}36,\;and\;36{\sim}48h$ intervals, 4.1%, 68.6%, 19.1%, and 2.3% oocytes were cleaved and 5.9% oocytes were not cleaved until 48 after activation. The cleaved oocytes in each interval were cultured and developed upto blastocyst with 0, 39.1, 9.5, and 0%, respectively. This results suggests that polar body extruded and cleaved at $12{\sim}36h$ embryo has higher developmental potential than the others.
Carcass traits are the most economically important traits in Hanwoo (Korean cattle). Recently, the development of the field of genomics has made it possible to identify DNA markers for the genetic evaluation of carcass and meat quality traits in beef cattle. The objective of this study was to assess the genetic effects of single nucleotide polymorphism (SNP) markers related to carcass traits by field evaluations in a commercial Hanwoo population. We evaluated 15 SNP markers (TG g.371T>C, APM1 g.1454G>A, FABP4 g.2834C>G, FABP4 g.3533T>A, FABP4 g.3691G>A, SCD g.10153A>G, SCD g.10329T >C, CPE g.601T>C, EDG1 g.166A>G, NPY g.4271T>C, GPD1 g.2766C>T, PDE1B g.17122A>G, PDE1B g.17507A>C, TNNT1 g.6650C>T, and RORC g.20152A>G) related to carcass traits in Hanwoo. Genotyping of these SNP markers was performed using PCR-RFLP analysis in Hanwoo steers (n = 1,536) to evaluate their association with carcass traits. Seven SNPs, APM1 g.1454G>, FABP4 g.3691G>A, SCD g.10153A>G, CPE g.601T>C, PDE1B g.17122A>G, TNNT1 g.6650C>T, and RORC g.20152A>G, were significantly associated with carcass traits such as marbling score (MS), backfat thickness (BF), musculus longissimus dorsi area (LDA), carcass weight (CW), meat grade (MG), meat color (MC), and maturity score (MA). The results suggest that these SNPs may be used as DNA markers for the selection of Hanwoo with higher meat quality.
Marbling (intramuscular fat) is an important factor in determining meat quality in Korean beef market. A grain based finishing system for improving marbling leads to inefficient meat production due to an excessive fat production. Identification of intramuscular fat-specific gene might be achieved more targeted meat production through alternative genetic improvement program such as marker assisted selection (MAS). We carried out ddRT-PCR in 12 and 27 month old Hanwoo steers and detected 300 bp PCR product of the inducible cAMP early repressor (ICER) gene, showing highly gene expression in 27 months old. A 1.5 kb sequence was re-sequenced using primer designed base on the Hanwoo EST sequence. We then predicted the open reading frame (ORF) of ICER gene in ORF finder web program. Tissue distribution of ICER gene expression was analysed in eight Hanwoo tissue using realtime PCR analysis. The highest ICER gene expression showed in Small intestine followed by Longissimus dorsi. Interestingly, the ICER gene expressed 2.5 time higher in longissimus dorsi than in same muscle type, Rump. For gene expression analysis in high- and low marbled individuals, we selected 4 and 3 animal based on the muscle crude fat contents (high is 17-32%, low is 6-7% of crude fat contents). The ICER gene expression was analysed using ANOVA model. Marbling (muscle crude fat contents) was affected by ICER gene (P=0.012). Particularly, the ICER gene expression was 4 times higher in high group (n=4) than low group (n=3). Therefore, ICER gene might be a functional candidate gene related to marbling in Hanwoo.
Journal of the korean academy of Pediatric Dentistry
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v.32
no.1
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pp.75-88
/
2005
Ameloblastoma is the most commonly occurring odontogenic tumor in oral cavity. Although most are benign epithelial neoplasm, they are generally considered to be locally aggressive and destructive, exhibiting a high rate of recurrence. The biological behavior of this neoplasm is a slowly growing, locally invasive tumor without metastasis, therefore malignant neoplasm, changed its histological appearance to carcinoma or showed distant metastasis, is only defined clinically. In this study, we identified the differentially expressed genes(DEGs) in stages under benign or malignant ameloblastoma compared with normal patient using ordered differential display(ODD) reverse transcription(RT)-PCR and $GeneFishing^{TM}$ technology. ODD RT-PCR is rather effective when the investigation of samples containing very small amounts of total RNA must be accomplished. ODD RT-PCR used the means of amplification with anchored T-primer and adaptor specific primer. bearing definite two bases at their 3' ends and so this method could display differential 3'-expressed sequence taqs(ESTs) patterns without using full-length cDNAs. Compared with standard differential display, ODD RT-PCR is more simple and have enough sensitivity to search for molecular markers by comparing gene expression profiles, However, this method required much effort and skill to perform. $GeneFishing^{TM}$ modified from DD-PCR is an improved method for detecting differentially expressed genes in two or more related samples. This two step RT-PCR method uses a constant reverse primer(anchor ACP-T) to prime the RT reaction and arbitrary primer pairs(annealing control primers, ACPs) during PCR. Because of high annealing specificity of ACPs than ODD RT-PCR, the application of $GeneFishing^{TM}$ to DEG discovery generates reproducible, authentic, and long(100bp to 2kb) PCR products that are detectable on agarose gels. Consequently, various DEGs observed differential expression levels on agarose gels were isolated from normal, benign, and malignant tissues using these methods. The expression patterns of the some isolated DEGs through ODD RT-PCR and $GeneFishing^{TM}$ were confirmed by Northern blot analysis and RT-PCR. The results showed that these identified DEGs were implicated in ameloblastoma neoplasm processes. Therefore, the identified DEGs will be further studied in order to be applied in candidate selection for marker as an early diagnosis during ameloblastoma neoplasm processes.
Kim, Seungchang;Kim, Kwanwoo;Roh, Heejong;Kim, Dongkyo;Kim, Sungwoo;Kim, Chalan;Lee, Sanghoon;Ko, Yeounggyu;Cho, Changyeon
Journal of the Korea Academia-Industrial cooperation Society
/
v.21
no.1
/
pp.240-246
/
2020
This study was conducted to develop specific Single Nucleotide Polymorphism (SNP) markers to identify the genetic characteristics and breed of White Hanwoo (WH) using a molecular biological method. SNP genotyping was performed with an Illumina Bovine HD 777K SNP chip using DNA extracted from 48 Hanwoo and 22 WH. The minor allele frequency (MAF) difference of each SNP was calculated and the statistical significance (P-value) of the MAF difference was calculated through Fisher's Exact test (Genotype). SNPs with 100% difference in the MAF difference were selected based on marker selection criteria. The nine SNP markers with genetic differences were selected. The selected markers have different alleles as being Hanwoo- and WH- specific. Therefore, based on these results, it can be concluded that the Hanwoo and WH varieties can be clearly distinguished by using these SNPs. So, the patent of the WH breed identification markers was registered. WH is a breed that shows the characteristics of a Korean native species that is separate from the native Hanwoo. It is expected that genetic characteristics research on the WH can be used to identify the breed and as a knowledge base for enhancing the value of breeding stock.
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