• 보존과학연구
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• s.23
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• pp.59-75
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• 2002

In this study human bones and teeth, excavated from the Myeongam-risite in Asan, Chungcheongnam-do Province, have been analysed by nuclear DNA typing and mitochondrial DNA sequencing methods. Twenty-one samples of long bones and twenty-seven samples of teeth from twenty-one individuals were collected and analysed. Among these thirteenteeth were successfully subjected to nuclear DNA extraction, quantification, and PCR(Polymerase Chain Reaction) amplification. Silver STR III (D16S539, D7S820, D13S317) multiplex PCR method was used in this study for a short tandem repeat (STR) analysis. Mitochondrial DNAs of tooth samples were also amplified and sequenced by a DNA sequencer. These analyses show that a sample from Burial no. 29 and one from Burial no. 38(right) possessed the same maternal inheritance. This may suggest that the Myeongam-ri cemetery was used by a kin group for a relatively long period of time.

• Journal of Genetic Medicine
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• v.3 no.1
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• pp.21-24
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• 1999

To study the X chromesome mosaicism in the cytogenetically pure 45,X Turner syndrome patients, we applied PCR technique using DNAs extracted from archived cytogenetic slides. We amplified the DNAs using nested primers targeted to a highly polymorphic short tandem repeat(STR) of the human androgen receptor gene(HUMARA) for the detection of X chromosome mosaicism. This assay is a very sensitive and useful method which can be applied to the DNAs extracted from archived cytogenetic slides to detect X mosaicism. We have tested 50 normal Korean females to determine whether the HUMARA locus is highly polymorphic among Koreans. 85% of Korean population showed heterozygosity in the HUMARA locus. We analysed the 24 DNAs extracted from archived slides of patients and abortuses with Turner syndrome in cytogenetic analysis. We observed the heterozygosities of 50% from pure 45,X patients, 83% from the patients with mosaic Turner syndrome and 8.3% from the abortuses of pure 45,X. Using the PCR technique of the HUMARA locus in the archived cytogenetic slides, we detected X chromosome mosaicism which could not be detected in cytogenetic analysis.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.59-66
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• 2010

Purpose: Quantitative fluorescent polymerase chain reaction (QF-PCR) allows for the rapid prenatal diagnosis of common aneuploidies. The main advantages of this assay are its low cost, speed, and automation, allowing for large-scale application. However, despite these advantages, it is not a routine method for prenatal aneuploidy screening in Korea. Our objective in the present study was to validate the performance of QF-PCR using short tandem repeat (STR) markers in a Korean population as a means for rapid prenatal diagnosis. Material and Methods: A QF-PCR assay using an Elucigene kit (Gen-Probe, Abingdon, UK), containing 20 STR markers located on chromosomes 13, 18, 21, X and Y, was performed on 847 amniotic fluid (AF) samples for prenatal aneuploidy screening referred for prenatal aneuploidy screening from 2007 to 2009. The results were then compared to those obtained using conventional cytogenetic analysis. To evaluate the informativity of STR markers, the heterozygosity index of each marker was determined in all the samples. Results: Three autosomes (13, 18, and 21) and X and Y chromosome aneuploidies were detected in 19 cases (2.2%, 19/847) after QF-PCR analysis of the 847 AF samples. Their results are identical to those of conventional cytogenetic analysis, with 100% positive predictive value. However, after cytogenetic analysis, 7 cases (0.8%, 7/847) were found to have 5 balanced and 2 unbalanced chromosomal abnormalities that were not detected by QF-PCR. The STR markers had a slightly low heterozygosity index (average: 0.76) compared to those reported in Caucasians (average: 0.80). Submicroscopic duplication of D13S634 marker, which might be a unique finding in Koreans, was detected in 1.4% (12/847) of the samples in the present study. Conclusion: A QF-PCR assay for prenatal aneuploidy screening was validated in our institution and proved to be efficient and reliable. However, we suggest that each laboratory must perform an independent validation test for each STR marker in order to develop interpretation guidelines of the results and must integrate QF-PCR into the routine cytogenetic laboratory workflow.

• Journal of Microbiology and Biotechnology
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• v.28 no.2
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• pp.338-346
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• 2018

Two molecular epidemiologic methods, IS6110 restriction fragment length polymorphism (IS6110-RFLP) and 24-locus mycobacterial interspersed repetitive unit-variable-number tandem repeat (MIRU-VNTR), are used worldwide in studies of Mycobacterium tuberculosis (MTB). Conversely, because of its poor resolution, pulsed-field gel electrophoresis (PFGE) is not widely used for MTB. In this study, we improved the 24-locus MIRU-VNTR and PFGE protocols and compared the effectiveness of these approaches for the molecular typing of MTB using 75 clinical isolates obtained from a cohort investigation of high-risk populations infected with MTB. The 24-locus MIRU-VNTR method demonstrated superior discriminatory ability, followed by PFGE and IS6110-RFLP. Next, we analyzed six isolates with clear epidemiologic connections; that is, isolates from patients who attended the same school. IS6110-RFLP and PFGE identified these samples as the same type. By contrast, according to MIRU-VNTR, two isolates differed from four other isolates at one locus each; one isolate was identified as Mtub29 and the other as QUB-26. In summary, the 24-locus MIRU-VNTR assay was the most useful molecular typing method among the three methods investigated due to its discriminatory power, short time required, and availability as an epidemiologic investigation tool. PFGE was the second-best method. Compared with the other loci assessed in the 24-locus MIRU-VNTR assay, the Mtub29 and QUB-26 loci appeared to exhibit greater variability during transmission.

• Molecules and Cells
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• v.25 no.2
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• pp.301-304
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• 2008

Microsatellites, short tandem repeats, are useful markers for genetic analysis because of their high frequency of occurrence over the genome, high information content due to variable repeat lengths, and ease of typing. To establish a panel of microsatellite markers useful for genetic studies of the Korean population, the allele frequencies and heterozygosities of 207 microsatellite markers in 119 unrelated Korean, Indian and Pakistani individuals were compared. The average heterozygosity of the Korean population was 0.71, similar to that of the Indian and Pakistani populations. More than 80% of the markers showed heterozygosity of over 0.6 and were valuable as genetic markers for genome-wide screening for disease susceptibility loci in these populations. To identify the allelic distributions of the multilocus genetic data from these microsatellite markers, the population structures were assessed by clustering. These markers supported, with the most probability, three clustering groups corresponding to the three geographical populations. When we assumed only two hypothetical clusters (K), the Korean population was separate from the others, suggesting a relatively deep divergence of the Korean population. The present 207 microsatellite markers appear to reflect the historical and geographical origins of the different populations as well as displaying a similar degree of variation to that seen in previously published genetic data. Thus, these markers will be useful as a reference for human genetic studies on Asians.

• Interdisciplinary Bio Central
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• v.2 no.4
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• pp.14.1-14.9
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• 2010

Misidentification of cultured cell lines results in the generation of erroneous scientific data. Hence, it is very important to identify and eliminate cell lines with a different origin from that being claimed. Various methods, such as karyotyping and isozyme analysis, can be used to detect inter-species misidentification. However, these methods have proved of little value for identifying intra-species misidentification, and it will only be through the development and application of molecular biological approaches that this will become practical. Recently, the profiling of microsatellite variants has been validated as a means of detecting gene polymorphisms and has proved to be a simple and reliable method for identifying individual cell lines. Currently, the human cell lines provided by cell banks around the world are routinely authenticated by microsatellite polymorphism profiling. Unfortunately, this practice has not been widely adopted for mouse cells lines. Here we show that the profiling of microsatellite variants can be also applied to distinguish the commonly used mouse inbred strains and to determine the strain of origin of cultured cell lines. We found that approximately 4.2% of mouse cell lines have been misidentified; this is a similar rate of misidentification as detected in human cell lines. Although this approach cannot detect intra-strain misidentification, the profiling of microsatellite variants should be routinely carried out for all mouse cell lines to eliminate inter-strain misidentification.

• Analytical Science and Technology
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• v.12 no.3
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• pp.260-264
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• 1999

A simple and rapid procedure, called FoLT-PCR(Formamide Low Temperature-Polymerase Chain Reaction) was applied to amplifying DNA directly from various forensic biological evidences including human blood, saliva, hair root, or semen without any DNA preparative steps. We added washing step with non-ionic detergent, 1% Triton X-100, and used Taq DNA polymerase instead of Tth DNA polymerase to amplify 3 STR loci and gender allele simultaneouly. Optimal concentration of formamide and annealing temperature were determined empirically to 8%(v/v), and $48^{\circ}C$ respectively. We also compared this method with standard PCR.

• Animal cells and systems
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• v.5 no.3
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• pp.237-241
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• 2001

Three STR loci (STRX1[AGAT]$_{n}$, HPRTB[AGAT]$_{n}$ and ARA[AGC]$_{n}$) on X chromosome and three other STR loci (DYS390[CTG(A)T]$_{n}$, DYS392[ATT]$_{n}$ and DYS39［GATA]$_{n}$) on Y chromosome were analyzed in 154 unrelated healthy Korean subjects. Four loci (STRX1, HPRTB, DYS390 and DYS393) were amplified by quadruplex polymerase chain reaction (PCR) using fluorescent labeled primers (FLP). ARA and DYS392 were amplified separately using single PCR, similarly by using FLP. They were then run in an automated DNA sequencer and were analyzed with Genescan software. We found 7 alleles (308-332 bp) in STRX1, 7 alleles (275-299 bp) in HPRTB, 16 alleles (252-315 bp) in ARA, 6 alleles (203-223 bp) in DYS390, 7 alleles (245-263bp) in DYS392 and 5 alleles (116-132 bp) in DYS393. The ＊13(34%), ＊13(5l%), ＊23 (l8%), ＊23(50%), ＊14(39%) and ＊13(40%) alleles were observed to be the highest frequencies of STRX1, HPRTB, ARA, DYS390, DYS392 and DYS393, respectively. The detection of STR loci on sex chromosomes by quadruplex PCR allows simple determination of sex and identification of an individual. individual.

• Journal of Genetic Medicine
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• v.12 no.1
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• pp.49-56
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• 2015

We herein report an analysis of a female baby with a de novo dup(10p)/del(10q) chromosomal aberration. A prenatal cytogenetic analysis was performed owing to abnormal ultrasound findings including a choroid plexus cyst, prominent cisterna magna, and a slightly medially displaced stomach. The fetal karyotype showed additional material attached to the terminal region of chromosome 10q. Parental karyotypes were both normal. At birth, the baby showed hypotonia, upslanting palpebral fissures, a nodular back mass, respiratory distress, neonatal jaundice and a suspicious polycystic kidney. We ascertained that the karyotype of the baby was 46,XX,der(10)($pter{\rightarrow}q26.3::p11.2{\rightarrow}pter$) by cytogenetic and molecular cytogenetic analyses including high resolution GTG-and RBG-banding, fluorescence in situ hybridization, comparative genomic hybridization, and short tandem repeat marker analyses. While almost all reported cases of 10p duplication originated from one of the parents with a pericentric inversion, our case is extraordinarily rare as the de novo dup(10p)/del(10q) presumably originated from a rearrangement at the premeiotic stage of the parental germ cell or from parental germline mosaicism.

• Genomics & Informatics
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• v.7 no.1
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• pp.32-37
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• 2009

The quality assurance (QA) is of utmost importance in biobanks when archived biomaterials are distributed to biomedical researchers. For sample authentication and cross-contamination detection, the two fundamental elements of QA, STR genotyping is usually utilized. However, the incorporated number of STR markers is highly redundant for biobanking purposes, resulting in time and cost inefficiency. An index to measure the cross-contamination detection capability of an STR marker, the mixture probability (MP), was developed. MP as well as other forensic parameters for STR markers was validated using STR genotyping data on 2328 normal Koreans with the commercial AmpFlSTR kit. For Koreans, 7 STR marker (D2S1338, FGA, D18S51, D8S1179, D13S317, D21S11, vWA) set was sufficient to provide discrimination power of ${\sim}10^{-10}$ and cross-contamination detection probability of ${sim}1$. Interestingly, similar marker sets were obtained from African Americans, Caucasian Americans, and Hispanic Americans under the same level of discrimination power. Only a small subset of commonly used STR markers is sufficient for QA purposes in biobanks. A procedure for selecting optimal STR markers is outlined using STR genotyping results from normal Korean population.