• Korean Journal of Veterinary Research
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• v.49 no.4
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• pp.319-328
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• 2009

This study investigated the epidemiology of Listeria (L.) monocytogenes, a food-borne pathogen. The epidemiology of food-borne pathogens is of great importance for clarifying bacterial origin and preventing bacterial contamination and infection. This work examined 68 L. monocytogenes strains, including 11 reference strains and 57 isolates from imported US beef, domestic meats (beef, pork, chicken meat), raw milk, and milk plants. The random amplified polymorphic DNA (RAPD) techniques were optimized to develop a standard molecular epidemiological analysis of L. monocytogenes. There was great genetic variability among the isolates, which produced 24 and 34 RAPD patterns with primer HLWL85 and HLWL74, respectively. The discriminatory power of the RAPD methods with HLWL85 and HLWL74 primer were very high (DI = 0.957; S ${\geq}$ 80%, S ${\geq}$ 95%). Some RAPD types were specific to origin. A few RAPD types were specific for L. monocytogenes strains belonging to a particular serotype. Using the HLWL85 primer, the strains isolated from milk plants could be distinguished from the other strains. And using the HLWL74 primer, the strains isolated from imported beef (US) could be distinguished completely from the other strains.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.12
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• pp.1822-1830
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• 2002

The microsatellites are the short tandem repeats of 1 to 6 bp long monomer sequences that are repeated several times. These short tandem repeats are considered to be generated by the slipped strand mispairing. Based on the unique capability of alternating purine-pyrimidine residues to form Z-DNA, the possible role of the microsatellites in gene regulation has been proposed. The microsatellites are highly polymorphic, follow Mendelian inheritance and are evenly distributed throughout the genomes of eukaryotes. They are easy to isolate and the polymerase chain reaction based typing of the alleles can be readily automated. These properties make them the preferred markers for comparison of the genetic structure of the closely related breeds/populations; very high-resolution genetic mapping and parentage testing etc. The microsatellites have rapidly replaced the restriction fragment length polymorphism (RFLP) and the random amplified polymorphic DNA (RAPD) in most applications in the population genetics studies in most species, including the various farm animals viz. cattle, buffalo, goat, sheep and pigs etc. More and more reports are now available describing the use of microsatellites in pigs ranging from measurement of genetic variation between breeds/populations, developing high resolution genetic maps to identifying and mapping genes of biological and economic importance.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.5 no.1
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• pp.94-107
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• 2005

Prenatal diagnosis (PND) such as amniocentesis or chorionic villi sampling has been widely used in order to prevent the birth of babies with defects especially in families with single gene disorderor chromosomal abnormalities. Preimplantation genetic diagnosis (PGD) has already become an alternative to traditional PND. Indications for PGD have expanded beyond those practices in PND (chromosomal abnormalities, single gene defects), such as late-onset diseases with genetic predisposition, and HLA typing for stem cell transplantation to affected sibling. After in vitro fertilization, the biopsied blastomere from the embryo is analyzed for single gene defect or chromosomal abnormality. The unaffected embryos are selected for transfer to the uterine cavity. Therefore, PGD has an advantage over PND as it can avoid the risk of pregnancy termination. In this review, PGD will be introduced and application of PGD in inborn error metabolic disorder will be discussed.

• Mycobiology
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• v.43 no.3
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• pp.360-365
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• 2015

Multilocus sequence typing analysis was applied to determine the genotypes of 147 (137 clinical and 10 environmental) Cryptococcus neoformans and three clinical Cryptococcus gattii isolates from 1993 to 2014 in Korea. Among the 137 clinical isolates of C. neoformans, the most prevalent genotype was ST5 (n = 131), followed by ST31 (n = 5) and ST127 (n = 1). Three C. gattii strains were identified as ST57, ST7, and ST113. All environmental isolates were identified as C. neoformans with two genotypes, ST5 (n = 7) and ST31 (n = 3). Our results show that C. neoformans isolates in Korea are genetically homogeneous, and represent a close genetic relationship between clinical and environmental isolates.

• Korean Journal of Veterinary Research
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• v.43 no.1
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• pp.25-29
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• 2003

This study was carried out to investigate a usefulness of the microsatellite DNA markers for parentage verification of Thoroughbred (TB) horses. 9 TB horses samples were genotyped for nine international minimum standard markers (AHT4, 5, ASB2, HMS3, 6, 7, HTG4, 10, and VHL20), and the additional panel of four markers, ASB17, CA425, LEX33, and TKY321. This methods consisted of multiplexing PCR procedures, and it showed reasonable amplification of all PCR products. Genotyping was performed with an ABI 310 genetic analyzer. Foal I was excluded according to principles of Mendelian genetics in AHT4 (H/K), ASB2 (Q/Q), HMS3 (I/P), HTG4 (M/O), HTG1O (K/R), VHL20 (M/P), ASB17 (F/N), LEX33 (M/O), and TKY321 (G/I) markets. Foal II was excluded with markers AHT5 (K/M), ASB2 (M/N), HMS7 (N/N), HTG1O (K/K), VHL20 (I/I), ASB17 (F/F) and TKY321 (G/I). Foal III was excluded with markers AHT4 (O/O), AHT5 (K/K), ASB2 (M/R), HMS6 (M/P), HMS7 (O/O), HTG10 (R/S), VHL20 (L/M), and ASB17 (N/O). These results suggest that the present DNA typing is so useful for parentage verification of TB horses.

• Journal of Genetic Medicine
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• v.15 no.2
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• pp.49-54
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• 2018

Nuchal translucency is an important indicator of an aneuploid fetus in prenatal diagnostics. Previously, only the presence of aneuploid could be confirmed by conventional karyotyping of fetuses with thick nuchal translucency. With the development of genetic diagnostic techniques, however, it has been reported that subtle variations not detectable by conventional karyo-typing might occur in cases of pathologic clinical syndrome in euploid fetuses. One of the newer, high-resolution genetic methods in the prenatal setting is chromosomal microarray. The possible association between nuchal translucency thickness with normal karyotype and submicroscopic chromosomal abnormalities detectable by microarray has been studied. How and when to apply microarray in clinical practice, however, is still debated. This article reviews the current studies on the clinical application of microarray in cases of increased nuchal translucency with normal karyotype for prenatal diagnosis.

• Biomedical Science Letters
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• v.4 no.1
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• pp.11-25
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• 1998

The HLA genes located in the short arm of chromosome 6 specify heterodimeric glycoproteins involved in the regulation of the immune response. Recently, in the elucidation of HLA polymorphism, serological and cellular typing methods have been replaced by DNA typing using polymerase chain reaction (PCR). The purpose of this study was to establish the HLA DNA typing methods and determine gene frequencies of HLA molecules in Koreans. PCR-SSP (sequence specific primers) and PCR-RFLP (restriction fragment length polymorphism) techniques were used for the analysis of HLA-A, -B, -C, DRBl genes and HLA-DQAl, DQBl, DPBl genes, respectively. The results of B-lymphoblastoid cells used for control experiment were consistent with the previous data identified in the 11th International Histocompatibility Workshop. Seventeen, 23, 16, 8, 16, 13 and 37 types of HLA-A, B, C, DQAl, DQBl, DPBl and DRBl alleles were found, respectively, in a total of unrelated 120 Korean individuals. The most frequent HLA alleles were $A^*$02 (27.0%), B$^*$40 (17.6%), Cw$^*$01 (19.2%), DQAl$^*$0301 (32.1%), DQBl$^*$0303 (12.9%), DPBl$^*$0501 (31.3%) and DRBl$^*$1501 (9.2%) among Koreans. This study shows that DNA typing method using PCR technique is a relatively simple, fast and practical tool for the determination of the HLA-class I and II genes. Moreover, the data of HLA gene frequencies could be useful for the Korean database before clinical applications, including organ and unrelated bone marrow transplantation, anthropological study, disease association and individual identification.

• Journal of Veterinary Clinics
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• v.23 no.2
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• pp.207-210
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• 2006

A probable case of superfetation in a Korean native cow met in a small farm located in Imsil Gun, Chonbuk. The cow delivered twice a living male and female calves in September 4 and December 9, 2004, respectively. Thus, we determined whether this case is a case of superfetation using parentage testing technique. The parentage testing was carried out for a dam and two calves using microsatellite DNA and blood typing. As the calves had at least one of the alleles on all marker tested that existed in dam, it was estimated that both of the calves were offsprings of the cow, and that they came from superfetation.

• Journal of Microbiology
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• v.43 no.5
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• pp.424-429
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• 2005

In previous studies, it has been reported that both S. enteritidis, the most common serotype, and S. enteritidis Phage Type 4 (SEPT 4) isolates were identified as the most prevalent PT in domestic poultry and also in humans in Korea until 2002. The aim of this study was to analyze the genetic diversity and epidemiological properties of both PT isolates, and also to trace the source of SEPT 4 isolates from domestic poultry and humans by Pulsed-field gel electrophoresis (PFGE). In order to understand the molecular epidemiologic properties of SEPT 4 isolates, which have very similar phenotypic properties to our preliminary investigations (serotyping, phage typing, large plasmids and antibiograms), PFGE analysis with XbaI enzyme was performed on the representative SEPT 4 isolates. Thirty-six SEPT 4 isolates were analyzed and differentiated with 10 pulsed-field profiles (PFP) expressing very high discriminative ability (SID: 0.921). In PFP, SEPT 4 isolates from human patients showed a perfect genetic match with those from broiler chickens and meats. Therefore, this study was able to successfully trace the major source of SEPT 4 isolates and also to determine the usefulness of the PFGE method for genetic analysis of epidemic strains.

• Journal of Microbiology and Biotechnology
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• v.20 no.10
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• pp.1457-1462
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• 2010

Three types of serotypically atypical Shigella flexneri isolates were collected between 2007 and 2008 from Korean patients at the Korea National Institute of Health (NIH). These atypical isolates were characterized and compared with serologically typical S. flexneri. The first grouping of 11 atypical isolates displayed agglutination only with polyB antiserum and exhibited no reaction with any typing or grouping sera (PolyB:un). The second group of 3 isolates displayed reactions with typing sera IV, but also did not bind with any grouping sera (IV:un). The third group of 14 isolates exhibited a plural agglutination pattern, reacting with typing sera II, and two grouping sera (II:(3)4,7(8)). Amongst these atypical isolates, isolates belonging to IV:un and II:(3)4,7(8) exhibited greater antibiotic resistance, in particular to ampicillin, streptomycin, and trimethoprim-sulfamethoxazole, than typical S. flexneri strains. Furthermore, all II:(3)4,7(8) strains harbored integrons. This study suggests that these multiple antibiotic-resistant atypical S. flexneri are new subserotypes of S. flexneri that await further serological classification.