• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.113-121
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• 2010

Mixture is that DNA profiles of samples contain material from more than one contributor, especially common in rape cases. In this situation, first, the method based on enumerating a complete set of possible genotype that may have generated the mixed DNA profile have been studied for interpreting DNA mixtures. More recently, the methods utilizing peak area information to calculate likelihood ratios have been suggested. This study is concerned with the analysis and interpretation of mixed forensic stains using quantitative peak area information and the method of forensic inference for extension of material from more than or equal to three contributors. Finally, the numerical example will be outlined.

• Journal of Oral Medicine and Pain
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• v.22 no.2
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• pp.253-260
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• 1997

한국인 집단에서 개인식별의 기초자료로 활용하고자 한국인 201명을 대상으로 STR 유전좌위 중 하나인 LPL 유전좌위의 유전자 빈도 및 유전자형 분포를 구하였다. 혈액으로부터 추출한 핵 DNA를 중합효소연쇄반응으로 증폭시키고 폴리아크릴아마이드 겔 상에서 전기영동하여 은염색한 후 관찰하여 다음의 결과를 얻었다. 1. 한국인 집단 201명의 LPL 유전자에서 5개의 대립유전자, 7개의 유전자형을 검출하였으며, 이형접합도는 50.7%로 나타났고 대립 유전자다양성 (allelic diversity value)은 0.454, 개 인식 별력 (PD)은 0.674를 보였다. 2. 대립 유전자 및 유전자빈도는 9, 10, 11, 12, 13 대립 유전자에서 각각 0.020, 0.714, 0.100, 0.164, 0.002로 나타났으며, 대립유전자 7, 8, 14는 관찰되지 않았다. 이상의 결과를 볼 때 한국인 집단에서 STR LPL유전좌위의 유전자빈도는 친자감정 등 개인식별에 유용하게 사용할 수 있으나 감정실무에 응용시 다수의 STR유전좌위 및 VNTR유전좌위의 분석을 병행하여야 할 것으로 사료된다.

• 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.

• 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.

• Genomics & Informatics
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• v.6 no.1
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• pp.14-17
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• 2008

GENDISCAN study (Gene Discovery for Complex traits in Asian population of Northeast area) was designed to incorporate methodologies which enhance the power to identify genetic variations underlying complex disorders. Use of population isolates as the target population is a unique feather of this study. However, population isolates may have hidden inbreeding structures which can affect the validity of the study. To understand how this issue may affect results of GENDISCAN, we estimated inbreeding coefficients in two study populations in Mongolia. We analyzed the status of Hardy-Weinberg Equilibrium (HWE), polymorphism information contents (PIC), heterozygosity, allelic diversity, and inbreeding coefficients, using 317 and 1,044 STR (short tandem repeat) markers in Orkhontuul and Dashbalbar populations. HWE assumptions were generally met in most markers (88.6% and 94.2% respectively), and single marker PIC ranged between 0.2 and 0.9. Inbreeding coefficients were estimated to be 0.0023 and 0.0021, which are small enough to assure that conventional genetic analysis would work without any specific modification. We concluded that the population isolates used in GENDISCAN study would not present significant inflation of type I errors from inbreeding effects in its gene discovery analysis.

• 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.

• The Journal of the Korea Contents Association
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• v.22 no.10
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• pp.733-741
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• 2022

Among the various evidence found in maritime crimes, fingerprints and DNA are very important in that they can identify a suspect. In this study, 5 types of non-porous surfaces (plastic, stainless, glass, ceramic, FRP), which are often found as evidence in the actual marine environment, were selected, and latent and blood fingerprints were passed down and immersed at the Donghae Maritime Police Station's exclusive pier for about 7 days. After that, DNA extraction, quantification, and STR profile were analyzed after fingerprint developing CA fumming method and 4 powder methods (Swedish black powder, Concentrated black powder, Supranano red powder, Dazzle orange powder). Among the fingerprint developing methods, when Supranano red powder was applied, a relatively high amount of DNA was found. As a result of STR profile analysis, an average of 16.8 to 9 loci were secured, and all 20 were confirmed in glass and ceramic materials. As a result of the study, it was possible to secure the STR profile by extracting and quantifying DNA after applying the fingerprint developing method to virtual evidence immersed for about 7 days, and further research is needed to secure the STR profile by analyzing DNA after applying various fingerprint developing methods such as VMD and SPR.

• 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.

• Animal Bioscience
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• v.35 no.4
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• pp.527-532
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• 2022

Objective: In this study, we aimed to investigate the recent changes such as allele frequencies and total probability of exclusion (PE) in Thoroughbred horses in Korea using short tandem repeat (STR) parentage panels between 2006 and 2016. Methods: The genotype was provided for 5,988 horse samples with 15 microsatellite markers (AHT4, AHT5, ASB2, ASB17, ASB23, CA425, HMS1, HMS2, HMS3, HMS6, HMS7, HTG4, HTG10, LEX3 and VHL20). Results: In our study, the observed number of alleles per locus ranged from 3 (HMS1) to 9 (ASB17) in 2006 and 4 (HMS1) to 9 (ASB2) in 2016, with a mean value of 6.28 and 6.40, respectively. Of the 15 markers, HMS2, HTG4, and CA425 loci had relatively low polymorphism information content (<0.5000) in the Thoroughbred population. Mean levels of genetic variation in 2006 and 2016 were observed heterozygosity (H_O) = 0.708, and expected heterozygosity (H_E) = 0.685, as well as and H_O = 0.699 and H_E = 0.682, respectively. The PE was calculated for each group based on the allele frequencies of 14 or 15 STRs. The 2006 survey analyzed that PE was 0.9998, but it increased to 0.9999 in 2016 after the HMS2 marker was added in 2011. The current STR panel is still a powerful tool for parentage verification that contributes to the maintenance of integrity in the Thoroughbred population. Conclusion: The current STR panel is still a powerful tool for parentage verification that contributes to the maintenance of integrity in the Thoroughbred horses. However, continuous monitoring genetic variability is necessary.