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Lee C.G.,Eulji General Hospital | Park S.-J.,MG MED Inc | Yun J.-N.,Ajou University | Ko J.M.,Ajou University | And 3 more authors.
Yonsei Medical Journal | Year: 2013

Porpose:This study analyzed and evaluated the demographic, clinical, and cytogenetic data [G-banded karyotyping and array-based comparative genomic hybridization (array CGH)] of patients with unexplained developmental delay or intellectual disability at a single Korean institution. Materials and Methods: We collected clinical and cytogenetic data based on retrospective charts at Ajou University Medical Center, Suwon, Korea from April 2008 to March 2012. Results: A total of 190 patients were identified. Mean age was 5.1±1.87 years. Array CGH yielded abnormal results in 26 of 190 patients (13.7%). Copy number losses were about two-fold more frequent than gains. A total of 61.5% of all patients had copy number losses. The most common deletion disorders included 22q11.2 deletion syndrome, 15q11.2q12 deletion and 18q deletion syndrome. Copy number gains were identified in 34.6% of patients, and common diseases among these included Potocki-Lupski syndrome, 15q11-13 duplication syndrome and duplication 22q. Abnormal karyotype with normal array CGH results was exhibited in 2.6% of patients; theses included balanced translocation (n=2), inversion (n=2) and low-level mosaicism (n=1). Facial abnormalities (p<0.001) and failure to thrive were (p<0.001) also more frequent in the group of patients with abnormal CGH findings. Conclusion: Array CGH is a useful diagnostic tool in clinical settings in patients with developmental delay or intellectual disability combined with facial abnormalities or failure to thrive. © Yonsei University College of Medicine 2013.


Sohn Y.B.,Ajou University | Lee C.G.,Eulji General Hospital | Ko J.M.,Seoul National University | Yang J.-A.,Ajou University | And 5 more authors.
Journal of Human Genetics | Year: 2013

Sotos syndrome is an overgrowth syndrome with characteristic facial dysmorphism, variable severity of learning disabilities and macrocephaly with overgrowth. Haploinsufficiency of the nuclear receptor SET domain-containing protein 1 (NSD1) gene located on 5q35 has been implicated as the cause of Sotos syndrome. This study was performed to investigate the mutation spectrum of NSD1 abnormalities and meaningful genotype-phenotype correlations in Korean patients with Sotos syndrome. Eighteen unrelated Korean patients with Sotos syndrome were enrolled for clinical and molecular analyses. Cytogenetic studies were performed to confirm 5q35 microdeletion, and NSD1 sequencing analysis was performed to identify intragenic mutations. NSD1 abnormalities were identified in 15 (83%) patients. Among them, eight patients (53%) had 5q35 microdeletions and the other seven patients (47%) had seven different NSD1 intragenic mutations including four novel mutations. The mutation spectrum of Korean patients with Sotos syndrome was similar to that of previous studies for Japanese patients. Height was significantly shorter and age of walking alone was significantly older in the microdeletion group compared with those in the intragenic mutation group. No significant differences were observed for other clinical characteristics between the microdeletion and intragenic mutation groups. Further studies with a larger number of patients will be necessary to draw conclusive genotype-phenotype correlations. © 2013 The Japan Society of Human Genetics All rights reserved.


Ko J.M.,Ajou University | Kim J.B.,Ajou University | Pai K.S.,Ajou University | Yun J.-N.,Ajou University | Park S.-J.,MG MED Inc.
Journal of Korean Medical Science | Year: 2010

The 22q11 region has been implicated in chromosomal rearrangements that result in altered gene dosage, leading to three different congenital malformation syndromes: DiGeorge syndrome, cat-eye syndrome (CES), and der(22) syndrome. Although DiGeorge syndrome is a common genomic disorder on 22q11, CES is quite rare, and there has been no report of Korean CES cases with molecular cytogenetic confirmation. In this study, we present the phenotypic and genetic characteristics of a 3-month-old boy with CES. Clinical findings included micropthalmia, multiple colobomata, and renal and genital anomalies. Cytogenetic analyses showed the presence of a supernumerary marker chromosome, which was identified as a bisatellited and isodicentric chromosome derived from an acrocentric chromosome. The results of array comparative genomic hybridization and fluorescence in situ hybridization studies confirmed the karyotype as 47,XY,+mar.ish idic(22)(q11.1) (D22S43+).arr 22q11.1(15,500,000-15,900,000)x4, resulting in a partial tetrasomy of 22q11.1. To the best of our knowledge, this is the first report in Korea of CES confirmed by cytogenetic and molecular cytogenetic analyses. © 2010 The Korean Academy of Medical Sciences.


Lee C.G.,Eulji General Hospital | Park S.-J.,MG MED Inc | Yun J.-N.,Ajou University | Yim S.-Y.,Ajou University | Sohn Y.B.,Ajou University
Journal of Korean Medical Science | Year: 2012

Deletion and duplication of the -3.7-Mb region in 17p11.2 result in two reciprocal syndrome, Smith-Magenis syndrome and Potocki-Lupski syndrome. Smith-Magenis syndrome is a well-known developmental disorder. Potocki-Lupski syndrome has recently been recognized as a microduplication syndrome that is a reciprocal disease of Smith-Magenis syndrome. In this paper, we report on the clinical and cytogenetic features of two Korean patients with Smith-Magenis syndrome and Potocki-Lupski syndrome. Patient 1 (Smith-Magenis syndrome) was a 2.9-yr-old boy who showed mild dysmorphic features, aggressive behavioral problems, and developmental delay. Patient 2 (Potocki-Lupski syndrome), a 17-yr-old boy, had only intellectual disabilities and language developmental delay. We used array comparative genomic hybridization (array CGH) and found a 2.6 Mb-sized deletion and a reciprocal2.1 Mb-sized duplication involving the 17p11.2. These regions overlapped in a 2.1 Mb size containing 11 common genes, including RAI1 and SREBF. © 2012 The Korean Academy of Medical Sciences.


Lee C.G.,Ajou University | Park S.-J.,MG MED Inc. | Yim S.-Y.,Ajou University | Sohn Y.B.,Ajou University
Brain and Development | Year: 2013

Potocki-Lupski syndrome (PTLS [MIM 610883]) is a recently recognized microduplication syndrome associated with 17p11.2. It is characterized by mild facial dysmorphic features, hypermetropia, infantile hypotonia, failure to thrive, mental retardation, autistic spectrum disorders, behavioral abnormalities, sleep apnea, and cardiovascular anomalies. In several studies, the critical PTLS region was deduced to be 1.3. Mb in length, and included RAI1 and 17 other genes. We report a 3-year-old Korean boy with the smallest duplication in 17p11.2 and a milder phenotype. He had no family history of neurologic disease or developmental delay and no history of seizure, autistic features, or behavior problems. He showed subtle facial dysmorphic features (dolichocephaly and a mildly asymmetric smile) and flat feet. All laboratory tests were normal and he had no evidence of internal organ anomalies. He was found to have mild intellectual disabilities (full scale IQ 65 on K-WPPSI) and language developmental delay (age of 2.2 year-old on PRESS). Array comparative genomic hybridization (CGH) showed about a 0.25 Mb microduplication on chromosome 17p11.2 containing four Refseq (NCBI reference sequence) genes, including RAI1 [arr 17p11.2(17,575,978-17,824,623) × 3]. When compared with previously reported cases, the milder phenotype of our patient may be associated with the smallest duplication in 17p11.2, 0.25 Mb in length. © 2012 The Japanese Society of Child Neurology.


Park S.-J.,MG MED Inc. | Jung E.H.,MG MED Inc. | Ryu R.-S.,MG MED Inc. | Kang H.W.,Macrogen Inc. | And 5 more authors.
Molecular Cytogenetics | Year: 2011

Background: Array comparative genomic hybridization (CGH) is currently the most powerful method for detecting chromosomal alterations in pre and postnatal clinical cases. In this study, we developed a BAC based array CGH analysis platform for detecting whole genome DNA copy number changes including specific micro deletion and duplication chromosomal disorders. Additionally, we report our experience with the clinical implementation of our array CGH analysis platform. Array CGH was performed on 5080 pre and postnatal clinical samples from patients referred with a variety of clinical phenotypes. Results: A total of 4073 prenatal cases (4033 amniotic fluid and 40 chorionic villi specimens) and 1007 postnatal cases (407 peripheral blood and 600 cord blood) were studied with complete concordance between array CGH, karyotype and fluorescence in situ hybridization results. Among 75 positive prenatal cases with DNA copy number variations, 60 had an aneuploidy, seven had a deletion, and eight had a duplication. Among 39 positive postnatal cases samples, five had an aneuploidy, 23 had a deletion, and 11 had a duplication. Conclusions: This study demonstrates the utility of using our newly developed whole-genome array CGH as first-tier test in 5080 pre and postnatal cases. Array CGH has increased the ability to detect segmental deletion and duplication in patients with variable clinical features and is becoming a more powerful tool in pre and postnatal diagnostics. © 2011 Park et al; licensee BioMed Central Ltd.


Park S.-J.,MG MED Inc. | Jung E.H.,MG MED Inc. | Ryu R.-S.,MG MED Inc. | Kang H.W.,Macrogen Inc. | And 2 more authors.
Molecular Cytogenetics | Year: 2013

Background: Array comparative genomic hybridization (CGH) is a powerful tool for detecting unbalanced chromosomal alterations. To validate the usefulness of array CGH in newborn screening, we examined 20,126 unselected infants. In addition, the number of newborns analyzed with array CGH is the largest one ever reported. Findings. A total of 20,126 unselected newborns were investigated with array CGH and cytogenetic analyses. The analyses revealed 87 cases with chromosome abnormalities. Of these, 53 cases had significant chromosome aneuploidies, including trisomy 13, trisomy 21, 47,XXY or 45,X, and the other 34 cases presented partial chromosomal deletions or duplications. Conclusions: In this study, we show that array CGH is an appropriate tool for the screening of chromosomal abnormalities in newborns, especially for the infants without distinct clinical features. © 2013 Park et al.; licensee BioMed Central Ltd.


Jeong S.-Y.,Ajou University | Park S.-J.,MG MED Inc. | Kim H.J.,Ajou University
Blood Cells, Molecules, and Diseases | Year: 2011

Gaucher disease (GD) is an autosomal recessive glycolipid lysosomal storage disease caused by a deficiency of the β-glucocerebrosidase enzyme (GBA). Allelic heterogeneity in GD has been well described. To date, more than 270 different GBA mutations have been reported. In order to determine the GBA mutation spectrum in Korean GD patients, we performed GBA mutation analysis of Korean patients and identified 72 GBA mutant alleles from 36 unrelated patients (100% identification), including 60 single-nucleotide substitutions, 6 single-nucleotide deletions, 4 recombinants, 1 splicing error, and 1 complex allele. N370S, the most common GBA mutation, was not detected, and most of the Korean GBA mutations were previously known to be rare, with the exception of L444P (~. 21%). Three mutations, P201H, F347L. +. L444P, and c.630delC, are novel. Examination of the GBA mutant alleles found in 6 ethnic groups revealed that the prevalences of GBA mutant alleles in Korean patients are very different from those seen in Jewish, non-Jewish Caucasian, and Italian patients, but similar to those seen in Japanese and Chinese patients. Our data may provide greater understanding of GBA allelic heterogeneity and an Asian perspective. 11Hyon J. Kim, Gaucher disease: an Asian perspective, Journal of Japanese Society for Inherited Metabolic Disease 20(1) (2004) 48-50. on correlations between genotypes and phenotypes, which may help further the development of better management strategies for patients with GD. © 2010.


Jeong S.-Y.,Ajou University | Park S.-J.,MG MED Inc. | Lee S.-J.,Ajou University | Park H.-J.,Ajou University | Kim H.J.,Ajou University
Journal of Korean Medical Science | Year: 2010

Neurofibromatosis type 1 (NF1) is one of the most commonly inherited autosomal dominant disorders. In order to determine whether genomic alterations and/or chromosomal aberrations involved in the malignant progression of NF1 were present in a Korean patient with NF1, molecular and cytogenetic analyses were performed on the pathologically normal, benign, and malignant tissues and primary cells cultured from those tissues of the patient. The comparative genomic hybridization (CGH) array revealed a Y chromosome loss in the malignant peripheral nerve sheet tumor (MPNST) tissue. G-banding analysis of 50 metaphase cells showed normal chromosomal patterns in the histopathologically normal and benign cultured cells, but a mosaic Y chromosome loss in the malignant cells. The final karyotype for the malignant cells from MPNST tissue was 45,X,-Y[28]/46,XY[22]. The data suggest that the somatic Y chromosome loss may be involved in the transformation of benign tumors to MPNSTs. © 2010 The Korean Academy of Medical Sciences.


PubMed | MG MED Inc
Type: Journal Article | Journal: Molecular cytogenetics | Year: 2013

Array comparative genomic hybridization (CGH) is a powerful tool for detecting unbalanced chromosomal alterations. To validate the usefulness of array CGH in newborn screening, we examined 20,126 unselected infants. In addition, the number of newborns analyzed with array CGH is the largest one ever reported.A total of 20,126 unselected newborns were investigated with array CGH and cytogenetic analyses. The analyses revealed 87 cases with chromosome abnormalities. Of these, 53 cases had significant chromosome aneuploidies, including trisomy 13, trisomy 21, 47,XXY or 45,X, and the other 34 cases presented partial chromosomal deletions or duplications.In this study, we show that array CGH is an appropriate tool for the screening of chromosomal abnormalities in newborns, especially for the infants without distinct clinical features.

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