• Journal of the korean academy of Pediatric Dentistry
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• v.31 no.3
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• pp.439-447
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• 2004

The aim of this study is to survey the frequency of mutans streptococci species and biotypes isolated from dental plaque in Korean children and the relationship between species and biotypes of mutans streptococci and dft index. Dental plaques were collected from the anterior and molar teeth of upper and lower jaws in the subjects, aged below 12 years old. A dental examination was performed for dft (decayed, filled, total) with the WHO caries diagnostic criteria. The mutans streptococci from the sample were cultured selectively on mitis salivarius-bacitracine (MSB) agar plate. For biotyping of mutans streptococci, biochemical test was performed. From the culture, bacterial genomic DNA was prepared for using of PCR template for the identification of mutans streptococci at the species-level. Forty strains of mutans streptococci were isolated from dental plagues of 40 patients. The biotype I (45%) and biotype IV (32.5%) were most frequently detected. The prevalence of S. mutans and S. sobrinus was 69% and 31%, respectively. There was no positive relationship between species and biotypes of mutans streptococci and dft index. Our results revealed that biotype I and S. mutans were frequently detected in Korean children and support that dental caries incidents by many causative factors not only bacterial factor.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4559-4565
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• 2013

Background: Methylenetetrahydrofolate reductase (MTHFR) is involved in DNA synthesis and repair. We here aimed to investigate two common polymorphisms, C677T and A1298C, with genotype and haplotype frequencies in colorectal cancer (CRC) cases among Jordanian. Materials and Methods: 131 CRC cases were studied for MTHFR C677T and A1298C polymorphisms, compared to 117 controls taken from the general population, employing the PCR-RFLP technique. Results: We found the frequency of the three different genotypes of MTHFR C677T among Jordanians to be CC: 61.7%, CT: 35.2%, and TT 3.1% among CRC cases and 50.9%, 38.8% and 10.3% among controls. Carriers of the TT genotype were less likely to have CRC (OR=0.25; 95%CI: 0.076-0.811; p=0.021) as compared to those with the CC genotype. Genotype analysis of MTHFR A12987C revealed AA: 38.9%, AC: 45%, and CC 16% among CRC cases and 37.4%, 50.4% and 12.2% among controls. There was no significant association between genetic polymorphism at this site and CRC. Haplotype analysis of MTHFR polymorphism at the two loci showed differential distribution of the TA haplotype (677T-1298A) between cases and controls. The TA haplotype was associated with a decreased risk for colorectal cancer (OR=0.6; 95% CI: 0.4-0.9, p=0.03). Conclusions: The genetic polymorphism of MTHFR at 677 and the TA haplotype may modulate the risk for CRC development among the Jordanian population. Our findings may reflect an importance of genes involved in folate metabolism in cancer risk.

• Korean Journal of Microbiology
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• v.45 no.2
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• pp.126-132
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• 2009

Legionella spp. is the causative agent of Legionellosis, which induces a potentially fatal form of pneumonia. With a concentrated performance during the summer of 2008, we secured 73 isolates from the water systems of 25 wards in Seoul. We analysed serotypes, pathogenic genes (Dot/Icm), and patterns of pulsed-field gel electrophoresis (PFGE) in an attempt to confirm relationships among them. Different from the previous year's pattern (2007), among the isolates, 69 were Legionella pneumophila and 4 were Legionella spp. The serotype distribution of Legionella pneumophila was sg1 43, sg6 9, sg5 8, sg3 8, and sg2 1. The serotype for the 4 Legionella spp. was Legionella nautarum. Most of the Legionella pneumophila had several pathogenic genes. On the other hand, the 4 Legionella spp. were defective in pathogenicity in genomic terms. The PFGE patterns of the serotypes showed a tendency for diversity of Legionella pneumophila and a close correlation with genetic pathogenicity.

• The Journal of Internal Korean Medicine
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• v.29 no.1
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• pp.32-41
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• 2008

Background : Monocyte chemoattractant protein-1(MCP-1), one of the CC chemokines, appears to play a significant role in asthma pathogenesis. It was reported that polymorphism in the MCP-1(-2518 A/G promoter) was associated with asthma in Caucasians, but the association of this polymorphism and asthma patients in the Korean population has not yet been clarified. Objective : We investigated the possible association between 2 polymorphisms (-2518 A/G promoter and Cys35Cys) and asthma patients in a Korean population. Materials and Methods : DNA samples were obtained from 86 Korean asthma patients and 270 healthy controls. MCP-1 genomic variants (-2518 A/G promoter and Cys35Cys polymorphism) were detected by PCR-RFLP. Level of MCP-1 was measured by ELISA for each genotype (n=8) (AA, AG, GG) and allele types of -2518 A/G promoter polymorphism for control subjects. Results : The Cys35Cys polymorphism was associated with asthma patients in Korean population [genotype distribution ($X^{2}=16.011$, P<0.001)]. Comparison of the two groups revealed no detectable differences in genotype and allele frequencies of the -2518 A/G polymorphism. Haplotype frequencies analysis revealed significant difference $(X^{2}=51.70$, P<0.001). MCP-1 serum level of subjects with G genotype of -2518 A/G promoter polymorphism was statistically higher than that with AA genotype (P<0.05). Conclusion : Our data indicate that no association exists between the MCP-1 -2518 A/G polymorphism and asthma susceptibility in the Korean population. However, it is noteworthy that the high prevalence of the -2518 G allele in the Korean population suggests a potentially important ethnic variation in the regulation of MCP-1 production. This variation must be considered in gene-association studies in different ethnic populations.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.299-310
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• 2005

The severe form of chronic periodontitis(CP) has been reported to be strongly associated with the presence of allele 2 of composite IL-1B(+3954) and IL-1A(+4845) genetic polymorphisms(genotype positive). However, other studies have reported conflicting findings. These might have resulted from differences in ethnic background and disease entities. The aim of this study was to determine the distribution of IL-1A(+4845), IL-1B(+3954), IL-1B(-511), and IL-1 RN(VNTR) genetic polymorphisms in children as a future Korean population. The study population consisted of 92 children from the Dept. of Pediatric Dentistry, Chonnam National University Hospital. Genomic DNA was obtained from buccal swab. The IL-1A(+4845), IL-1B(+3954), and IL-1B(-511) genes were genotyped by amplifying the polymorphic region using multiplex polymerase chain reaction(PCR), followed by restriction enzyme digestion and gel electrophoresis. IL-1 RN(VNTR) polymorphism were then evaluated by PCR amplification and fragment size analysis in agarose gel. The allele 2 frequency was 41.3%, 4.3%, 47.8%, and 9.9% for IL-1A(+4845), IL-1B(+3954), IL-1B(-511), and IL-1 RN respectively. The frequency of genotype with allele 2 carriage for IL-1A(+4845), IL-1B(+3954), IL-1B(-511), and IL-1 RN was 77.1%, 7.6%, 63.0%, and 15.2% respectively. The allele 2 frequency in IL-1B(+3954) was significantly higher in female than in male population(p<0.05). The negative association was shown between the presence of allele 2 in IL-1B(-511) and in IL-1B(+3954), and the carriage rate of IL-1B(+3954) allele 2 tended to lower in IL-1B(-511) allele 2(P=0.056). Only 7.3% of children carried the composite genotype of IL-1A(+4845) and IL-1B(+3954). These results suggest that the polymorphism of IL-1B(+3954) and the positive composite genotype was relatively rare in Korean population.

• Journal of Life Science
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• v.29 no.6
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• pp.637-644
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• 2019

This study was conducted to analyze the genetic characteristics of the Jeju dog for preservation and protection. A total of 139 dogs from 7 dog breeds, including the Jeju dog, were genotyped using 16 microsatellite markers. The results revealed 2-18 alleles per locus, with a total of 131 alleles among the 16 markers. Most alleles were identified for FH3381, which had 18 alleles, whereas FH2834 had the fewest alleles, with just 2. When the total mean value was observed, the expected heterozygosity and observed heterozygosity were higher for than for outgroup dogs, and the PIC values ranged from 0.000 to 0.862, respectively. The phylogenetic tree analysis of the Jeju dog and other dog varieties revealed that the Jeju dog is closest to the Sapsal dog (0.393). The phylogeny between the Jeju and Korean domestic dogs showed that the Jeju dog is most distant from the Dongkyung dog (0.507). Looking at the distribution individually, the Jeju dog is in the same group as the Labrador Retriever and the Sapsal dog. Meanwhile, the Poongsan, Dongkyung, and Jindo dogs and the German Shepherd were in the same group. Genetic information confirmed through the results of this study can be used as basic data to study the genetic characteristics of the Jeju dog.

• The Korea Journal of Herbology
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• v.24 no.4
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• pp.115-120
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• 2009

Objectives : Due to the morphological similarity and frequent occurrence of intermediate forms as well as morphological variations of aerial part, the correct identification between Rhei Radix et Rhizoma and Rhei Undulatai Rhizoma is very difficult. To develop a reliable method for correct identification and improving the quality standards of Rhei Radix et Rhizoma and Rhei Undulatai Rhizoma, we analyzed RAPD and developed SCAR marker. Methods : To amplify target DNA at the genomic level, 32 Operon 10-mer random primers were applied with four Rheum species, R. officinale, R. palmatum, R. tanguticum and R. undulatum. The nucleotide sequences were determined and species-specific primers were prepared depending on the species-specific RAPD amplicons after subcloned into the pGEM-Teasy vector. To develop the SCAR markers, species-specific PCR amplification and multiplex-PCR were carried out using the single species-specific primer pairs and combinations of them, respectively. Results : We used RAPD analysis of four Rheum plant species to obtain several species-specific RAPD amplicons. From nucleotide sequences of these RAPD amplicons, we developed two SCAR markers that amplified 314 bp and 390 bp DNA fragments in only R. undulatum but not in R. officinale, R. palmatum, R. tanguticum and R. undulatum, for distinguishing Rhei Undulatai Rhizoma and Rhei Radix et Rhizoma. Furthermore, we established SCAR markers for the simultaneous discrimination of the three species within a single reaction by using multiplex-PCR. Conclusions : These genetic markers can be used for the efficient discrimination of plants species and commercial herbal medicines between Rhei Undulatai Rhizoma and Rhei Radix et Rhizoma, to ultimately prevent indiscriminate distribution and prescription of these herbal medicines.

• Journal of Life Science
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• v.22 no.12
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• pp.1644-1650
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• 2012

The aim of this study was to screen the polymorphisms and distribution of each genotype of insertion/ deletion (indel) markers which were found in a preliminary comparative study of bovine genomic sequence databases. Comparative bioinformatic analyses were first performed between the nucleotide sequences of Bovine Genome Project and those of expressed sequence tag (EST) database, and a total of fifty-one species of indel markers were screened. Of these, forty-two indel markers were evaluated, and nine informative indel markers were ultimately selected for population analysis. Nucleotide sequences of each marker were re-sequenced and their polymorphic patterns were typed in six cattle breeds: Holstein, Angus, Charolais, Hereford, and two Korean native cattle breeds (Hanwoo and Jeju Black cattle). Cattle breeds tested in this study showed polymorphic patterns in eight indel markers but not in the Indel-15 marker in Charolais and Holstein. The results of analysis for Jeju Black cattle (JBC) population indicated an observed heterozygosity (Ho) that was highest in HW_G1 (0.600) and the lowest in Indel_29 (0.274). The PIC value was the highest in HW_G4 (0.373) and lowest in Indel_6 (0.305). These polymorphic indel markers will be useful in supplying genetic information for parentage tests and traceability and to develop a molecular breeding system for improvement of animal production in cattle breeds as well as in the JBC population.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.27-28
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• 2014

Beauveria bassiana (Cordycipitaceae, Hypocreales, Ascomycota) is an anamorphic fungus having a potential to be used as a biological control agent because it parasitizes a wide range of arthropod hosts including termites, aphids, beetles and many other insects. A number of bioactive secondary metabolites (SMs) have been isolated from B. bassiana and functionally verified. Among them, beauvericin and bassianolide are cyclic depsipeptides with antibiotic and insecticidal effects belonging to the enniatin family. Non-ribosomal peptide synthetases (NRPSs) play a crucial role in the synthesis of these secondary metabolites. NRPSs are modularly organized multienzyme complexes in which each module is responsible for the elongation of proteinogenic and non-protein amino acids, as well as carboxyl and hydroxyacids. A minimum of three domains are necessary for one NRPS elongation module: an adenylation (A) domain for substrate recognition and activation; a tholation (T) domain that tethers the growing peptide chain and the incoming aminoacyl unit; and a condensation (C) domain to catalyze peptide bond formation. Some of the optional domains include epimerization (E), heterocyclization (Cy) and oxidation (Ox) domains, which may modify the enzyme-bound precursors or intermediates. In the present study, we analyzed genomes of B. bassiana and its allied species in Hypocreales to verify the distribution of NRPS-encoding genes involving biosynthesis of beauvericin and bassianolide, and to unveil the evolutionary processes of the gene clusters. Initially, we retrieved completely or partially assembled genomic sequences of fungal species belonging to Hypocreales from public databases. SM biosynthesizing genes were predicted from the selected genomes using antiSMASH program. Adenylation (A) domains were extracted from the predicted NRPS, NRPS-like and NRPS-PKS hybrid genes, and used them to construct a phylogenetic tree. Based on the preliminary results of SM biosynthetic gene prediction in B. bassiana, we analyzed the conserved gene orders of beauvericin and bassianolide biosynthetic gene clusters among the hypocrealean fungi. Reciprocal best blast hit (RBH) approach was performed to identify the regions orthologous to the biosynthetic gene cluster in the selected fungal genomes. A clear recombination pattern was recognized in the inferred A-domain tree in which A-domains in the 1st and 2nd modules of beauvericin and bassianolide synthetases were grouped in CYCLO and EAS clades, respectively, suggesting that two modules of each synthetase have evolved independently. In addition, inferred topologies were congruent with the species phylogeny of Cordycipitaceae, indicating that the gene fusion event have occurred before the species divergence. Beauvericin and bassianolide synthetases turned out to possess identical domain organization as C-A-T-C-A-NM-T-T-C. We also predicted precursors of beauvericin and bassianolide synthetases based on the extracted signature residues in A-domain core motifs. The result showed that the A-domains in the 1st module of both synthetases select D-2-hydroxyisovalerate (D-Hiv), while A-domains in the 2nd modules specifically activate L-phenylalanine (Phe) in beauvericin synthetase and leucine (Leu) in bassianolide synthetase. antiSMASH ver. 2.0 predicted 15 genes in the beauvericin biosynthetic gene cluster of the B. bassiana genome dispersed across a total length of approximately 50kb. The beauvericin biosynthetic gene cluster contains beauvericin synthetase as well as kivr gene encoding NADPH-dependent ketoisovalerate reductase which is necessary to convert 2-ketoisovalarate to D-Hiv and a gene encoding a putative Gal4-like transcriptional regulator. Our syntenic comparison showed that species in Cordycipitaceae have almost conserved beauvericin biosynthetic gene cluster although the gene order and direction were sometimes variable. It is intriguing that there is no region orthologous to beauvericin synthetase gene in Cordyceps militaris genome. It is likely that beauvericin synthetase was present in common ancestor of Cordycipitaceae but selective gene loss has occurred in several species including C. militaris. Putative bassianolide biosynthetic gene cluster consisted of 16 genes including bassianolide synthetase, cytochrome P450 monooxygenase, and putative Gal4-like transcriptional regulator genes. Our synteny analysis found that only B. bassiana possessed a bassianolide synthetase gene among the studied fungi. This result is consistent with the groupings in A-domain tree in which bassianolide synthetase gene found in B. bassiana was not grouped with NRPS genes predicted in other species. We hypothesized that bassianolide biosynthesizing cluster genes in B. bassiana are possibly acquired by horizontal gene transfer (HGT) from distantly related fungi. The present study showed that B. bassiana is the only species capable of producing both beauvericin and bassianolide. This property led to B. bassiana infect multiple hosts and to be a potential biological control agent against agricultural pests.

• Clinical and Experimental Pediatrics
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• v.45 no.7
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• pp.884-890
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• 2002

Purpose : Henoch-Schonlein purpura(HSP) nephritis has been reported to vary from 25 to 50% among HSP patients and is a common cause of chronic glomerulonephritis in children. In our study, we evaluated the distribution and the association of the Insertion/Deletion(I/D) polymorphism of angiotensin converting enzyme(ACE) gene with clinical manifestations, particularly proteinuria in children with HSP nephritis, compared with that in HSP. Methods : ACE gene polymorphism was determined in children with HSP nephritis(n=33) and HSP(n=28) who were diagnosed in Busan Paik hospital from January 1996 to June 2001. The I/D polymorphism of ACE gene was determined by PCR amplication of genomic DNA. Results : The ACE I/D genotype frequency was DD : 25%, ID : 50%, II : 25% in HSP and DD : 24 %, ID : 46%, II : 30% in HSP nephritis, there was no significant difference in the genotype and allele frequencies between two groups. When statistical analysis was done according to the presence of D allele, the amount of 24-hour urinary protein excretion and the incidence of moderate to heavy proteinuria(>$500mg/m^2/day$) at onset and last follow-up were higher in DD/ID genotype than in those in II genotype, but these differences were not statistically significant. Conclusion : We suggest a lack of association between I/D polymorphism of ACE gene and clinical manifestations in children with HSP nephritis. However, further follow-up studies based on a sufficient number of patients and long term follow up periods are necessary to confirm the role of I/D polymorphism of ACE gene in children with HSP nephritis.