• Annals of Clinical Neurophysiology
• /
• 제6권1호
• /
• pp.61-63
• /
• 2004

The copy numbers of the CTG repeats are known to relate to the severity of clinical symptoms for myotonic dystrophy. The positive correlation between clinical manifestations and CTG repeat size has been demonstrated previously. A genetically confirmed myotonic dystrophy patient with 90 CTG repeat number had more severe clinical manifestation than brother with 120 CTG repeats, in adulthood.

• Journal of Genetic Medicine
• /
• 제12권2호
• /
• pp.61-65
• /
• 2015

Whole genome sequencing (WGS)-based noninvasive prenatal test (NIPT) is the first method applied in the clinical setting out of various NIPT techniques. Several companies, such as Sequenom, BGI, and Illumina offer WGS-based NIPT, each with different technical and bioinformatic approaches. Sequenom, BGI, and Illumina utilize z-, t-, and L-scores, as well as normalized chromosome values, respectively, for trisomy detection. Their outstanding performance has been demonstrated in clinical studies of more than 100,000 pregnancies. The sensitivity and specificity for detection of trisomies 13, 18, and 21 were above 98%, as reported by all three companies. Unlike other techniques, WGS-based NIPT can detect other trisomies as well as clinically significant segmental duplications/deletions within a chromosome, which could expand the scope of NIPT. Incorrect results could be due to low fetal fraction, fetoplacental mosaicism, confined placental mosaicism or maternal copy number variation (CNV). Among those, maternal CNV is a significant contributor of false positive results and therefore genome wide scanning plays an important role in preventing the occurrence of false positives. In this article, the bioinformatic techniques and clinical performance of three major companies are comprehensively reviewed.

• Journal of Genetic Medicine
• /
• 제18권2호
• /
• pp.101-104
• /
• 2021

Xp21 contiguous gene deletion syndrome is associated with complex glycerol kinase deficiency, congenital adrenal hypoplasia, Duchene muscular dystrophy, and intellectual disability. Xp21 gene deletion syndrome is X-linked recessive, so most symptomatic patients are male, and only a few female symptomatic patients have been reported. We report the first female Korean case of an Xp21 deletion. NGS data were analyzed for copy number variation, and the Xp21 deletion (chr X: 29301056-31838200) was confirmed using real-time PCR.

• 한국정보처리학회:학술대회논문집
• /
• 한국정보처리학회 2008년도 추계학술발표대회
• /
• pp.356-359
• /
• 2008

최근 생물정보학 분야에서 인간 유전체에 존재하는 CNV(copy number variation)에 관한 연구가 주목 받고 있다. CNV 영역은 1kbp-3Mbp 사리의 서열이 반복되거나 결실되는 변이 영역으로 정의된다. 우리는 선행연구에서 기가 시퀀싱(giga sequencing)의 결과 산출되는 DNA 서열조각인 리드(read)를 레퍼런스 시퀀스에 서열 정렬하여 CNV 영역을 찾아내는 새로운 CNV 검색 방식을 제안하였다. 후속 연구로서 본 논문에서는 DNA 서열에 존재하는 repeat 영역 문제를 해결하기 위한 새로운 방안을 제안하고, 리드의 출현 빈도 정보를 분석하여 CNV 영역을 찾아내는 CNV 영역 검색 알고리즘을 보인다. 제안된 알고리즘 Gaussian 분포를 갖는 출현 빈도 정보로부터 통계적 유의성을 갖는 영역을 추출하여 CNV 영역후보로 하고, 다음 경제 과정을 거쳐 최종의 CNV 영역을 추출한다. 성능 평가를 위하여 프로토타임 시스템을 개발하였으며, 시뮬레이션 실험을 수행하였다. 실험 결과에 의하여 제안된 방식은 반복되거나 결실되는 형태의 CNV 영역을 효율적으로 검출하며, 또한 다양한 크기의 CNV 영역을 효율적으로 검출할 수 있음을 입증한다.

• Molecules and Cells
• /
• 제27권2호
• /
• pp.205-209
• /
• 2009

The loci of the 5S and 45S rRNA genes were localized on chromosomes in five species of Capsicum, namely, annuum, chacoense, frutescens, baccatum, and chinense by FISH. The 5S rDNA was localized to the distal region of one chromosome in all species observed. The number of 45S rDNA loci varied among species; one in annuum, two in chacoense and frutescens, and chinense, and four in baccatum, with the exceptions that 'CM334' of annuum had three loci and 'tabasco' of frutescens gad one locus. 'CM334'-derived BAC clones, 384B09 and 365P05, were screened with 5S rDNA as a probe, and BACs 278M03 and 262A23 were screened with 25S rDNA as a probe. Both ends of these BAC clones were sequenced. FISH with these BAC probes on pachytenes from 'CM334' plant showed one 5S rDNA locus and three 45S rDNA loci, consistent with the patterns on the somatic chromosomes. The 5S rDNA probe was also applied on extended DNA fibers to reveal that its coverage measured as long as 0.439 Mb in the pepper genome. FISH techniques applied on somatic and meiotic chromosomes and fibers have been established for chili to provide valuable information about the copy number variation of 45S rDNA and the actual physical size of the 5S rDNA in chili.

• Journal of Animal Science and Technology
• /
• 제49권5호
• /
• pp.559-568
• /
• 2007

최근 들어 유전자 또는 DNA 분절의 반복수 변이 (CNV)에 관한 연구가 다수 수행되었으며, 그 분석 방법 및 기기 또한 다양하게 발달되었다. 본 연구는 Landrace 품종의 KIT 유전자 CNV 탐지를 위하여 다른 분석 방법들에 비하여 정확도가 높은 정량적 OLA 기법(qOLA)을 이용하였다. qOLA와 pyrosequencing assay의 조합하여 분석한 결과를 Landrace 44두에 대한 좌표 분석을 한 결과 I1/I1 또는 I3/i(IBe), I1/I2 또는 I3/IP, I1/I3, I1/IP 또는 I2/i(IBe), I2/I2, I2/IP의 6 genotype으로 분류되었으며, PROC FASTCLUS procedure을 이용한 통계 분석과 좌표 분석을 상호 비교한 결과 genotype의 분류가 100% 일치하였다. 기기간의 차이점을 조사하기 위해 qOLA_3100과 qOLA _3130의 관측치 비교를 실시한 결과 동일한 genotype 분류결과를 얻었다. 또한 정밀성 및 정확도 비교에서 qOLA_3100의 경우 표준편차와 변이계수의 평균이 2.33과 4.10로 qOLA_3130(2.67과 4.81)에 비하여 낮게 나타났다. qOLA 반응전 PCR 산물에 대하여 proteinase K 처리효과를 분석한 결과 pro- teinase K를 처리한 경우 전기영동 분석시 noise peak들이 제거되었으며 각 genotype의 이론적 비율에 보다 정확히 일치하였다.

• Genomics & Informatics
• /
• 제9권4호
• /
• pp.152-160
• /
• 2011

Hypertension is the major factor of most death and high blood pressure (BP) can lead to stroke, myocardial infarction and cardiac failure. Moreover, hypertension is strongly correlated with body mass index (BMI). Although the exact causes of hypertension are still unclear, some of genetic loci were discovered from genome-wide association study (GWAS). Therefore, it is essential to study genetic variation for finding more genetic factor affecting hypertension. The purpose of our study is to conduct a CNV association study for hypertension-related traits, BP and BMI, in Korean individuals. We identified 2,206 CNV regions from 3,274 community-based Korean participants using the Affymetrix Genome-Wide Human SNP Array 6.0 platform and performed a logistic regression analysis of CNVs with two hypertension-related traits, BP and BMI. Moreover, the 4,692 participants in an independent cohort were selected for respective replication analyses. GWAS of CNV identified two loci encompassing previously known hypertension-related genes: LPA (lipoprotein) on 6q26, and JAK2 (Janus kinase 2) on 9p24, with suggestive p-values (0.0334 for LPA and 0.0305 for JAK2 ). These two positive findings, however, were not evaluated in the replication stage. Our result confirmed the conclusion of CNV study from the WTCCC suggesting weak association with common diseases. This is the first study of CNV association study with BP and BMI in Korean population and it provides a state of CNV association study with common human diseases using SNP array.

• 대한임상검사과학회지
• /
• 제55권1호
• /
• pp.16-28
• /
• 2023

폐암은 크게 소세포성 폐암과 비소세포성 폐암으로 구분되며 비소세포성폐암이 차지하는 비율은 약 70%~80%이다. 비소세포성폐암 중 폐선암은 전체 폐암의 약 40%를 차지한다. 최근 유전자 프로파일링 기술이 발전하면서 종양의 발생 및 성장에 중요한 종양 유전자와 종양 억제 유전자의 변이에 대한 연구가 활발히 진행되어 폐암을 유발하는 특정 유전자들이 발견되면서 생존율에 큰 영향을 미치게 되었으며 특히 폐선암은 차세대 염기서열 분석법(next generation sequencing, NGS)을 이용한 동반진단을 통해 표적 치료로 생존을 높이는 데 도움을 얻을 수 있다. 본 연구는 한국인에서 폐선암을 유발하는 유전자 변이 검출을 위해 비소세포성폐암 환자의 파라핀 포매조직(formalin-fixed paraffin-embedded)으로 hematoxylin and eosin 염색을 시행하여 폐선암을 구분하였으며 정확한 폐선암 조직을 분류하기 위해 면역조직화학(immunohistochemistry, IHC)염색을 시행하였다. 그 결과를 바탕으로 NGS를 이용하여 유전자 변이의 종류와 패턴을 분석하였고 폐암을 유발하는 가장 대표적인 원인인 흡연과의 관계를 확인하였다. NGS 결과 단일염기서열변이(single nucleotide variation, SNV), 복제수변이 (copy number variation, CNV), 유전자 재배열을 확인하였으며 폐선암에서 SNV는 TP53 (44.6%), EGFR (35.7%), KRAS (10.7%), PIK3CA (6.2%), CDKN2A (4.4%) 순으로 발생하였고 CNV의 경우 EGFR (14%)이 가장 빈번하게 발생하였다. 또한 ALK, ROS1, RET 과 같은 유전자 재배열을 확인하였다. NGS의 신뢰도를 확인을 위하여 기존에 사용되고 있는 유전자 검사방법인 PCR-EGFR, IHC-ALK (D5F3), FISH-ROS1 검사를 추가적으로 시행하여 NGS 결과와 일치도를 확인하였다. 이 연구는 폐선암 환자에 대한 NGS가 여러 유전자의 돌연변이를 동시에 확인하여 치료 전략에 더욱 긍정적인 이익을 줄 수 있음을 보여준다.

• Parasites, Hosts and Diseases
• /
• 제47권2호
• /
• pp.83-91
• /
• 2009

The completion of many malaria parasite genomes provides great opportunities for genomewide characterization of gene expression and high-throughput genotyping. Substantial progress in malaria genomics and genotyping has been made recently, particularly the development of various microarray platforms for large-scale characterization of the Plasmodium falciparum genome. Microarray has been used for gene expression analysis, detection of single nucleotide polymorphism (SNP) and copy number variation (CNV), characterization of chromatin modifications, and other applications. Here we discuss some recent advances in genetic mapping and genomic studies of malaria parasites, focusing on the use of high-throughput arrays for the detection of SNP and CNV in the P. falciparum genome. Strategies for genetic mapping of malaria traits are also discussed.

• Genomics & Informatics
• /
• 제8권3호
• /
• pp.101-102
• /
• 2010

During the last decade, large community cohorts have been established by the Korea National Institutes of Health (KNIH), and enormous epidemiological and clinical data have been accumulated. Using these information and samples in the cohorts, KNIH set out to do a large-scale genome-wide association study (GWAS) in 2007, and the Korea Association REsource (KARE) consortium was launched to analyze the data to identify the underlying genetic risk factors of diseases and diverse health indexes, such as blood pressure, obesity, bone density, and blood biochemical traits. The consortium consisted of 6 research divisions, formed by 25 principal investigators in 19 organizations, including 18 universities, 2 institutes, and 1 company. Each division focused on one of the following subjects: the identification of genetic factors, the statistical analysis of gene-gene interactions, the genetic epidemiology of gene-environment interactions, copy number variation, the bioinformatics related to a GWAS, and a GWAS of nutrigenomics. In this special issue, the study results of the KARE consortium are provided as 9 articles. We hope that this special issue might encourage the genomics community to share data and scientists, including clinicians, to analyze the valuable Korean data of KARE.