• Journal of Genetic Medicine
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• v.15 no.2
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• pp.55-63
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• 2018

Clinical and genetic heterogeneity in association with overlapping spectrum is characteristic in pediatric neuromuscular disorders, which makes confirmative diagnosis difficult and time consuming. Considering evolution of molecular genetic diagnosis and resultant upcoming genetically modifiable therapeutic options, rapid and cost-effective genetic testing should be applied in conjunction with existing diagnostic methods of clinical examinations, laboratory tests, electrophysiologic studies and pathologic studies. Earlier correct diagnosis would enable better clinical management for these patients in addition to new genetic drug options and genetic counseling.

• Journal of Interdisciplinary Genomics
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• v.4 no.1
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• pp.11-14
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• 2022

Primary ciliary dyskinesia (PCD) is a genetic disorder that affects approximately 1 in 15,000-30,000 people, with the majority of patients inheriting the disorder via autosomal recessive inheritance. PCD is characterized by abnormal ciliary ultrastructure and/or function, which results in impaired mucociliary clearance and recurrent respiratory infections. Despite the presence of symptoms from birth, many patients with PCD remain undiagnosed until adulthood. Many advances in the diagnosis of PCD have occurred in recent years, including nasal nitric oxide assays, ciliary motility tests, and genetic sequencing. Early diagnosis and symptom management may reduce morbidity and mortality from PCD improving the patient's quality of life.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.5 no.1
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• pp.108-115
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• 2005

Inherited metabolic diseases (IMD) comprise a large class of genetic diseases involving disorders of metabolism. The majorities are due to defects of single genes that code for enzymes that facilitate conversion of various substances into others. Because of the multiplicity of conditions, many different diagnostic tests are used for screening of IMD. Molecular genetic diagnosis is the detection of pathogenic mutations in DNA and/or RNA samples and is becoming a much more common practice in medicine today. The purpose of molecular genetic testing in IMD includes diagnostic testing, pre-symptomatic testing, carrier screening, prenatal diagnosis, preimplantation testing, and population screening. However, because of the complexity, difficulty in interpreting the result, and the ethical considerations, an understanding of technical, conceptual, and practical aspects of molecular genetic diagnosis is mandatory.

• Journal of Genetic Medicine
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• v.7 no.1
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• pp.16-23
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• 2010

Many endocrine disorders have a genetic component. The genetic component is the major etiologic factor in monogenic disorders, while multiple genes in conjunction with environmental and lifestyle factors contribute to the pathogenesis in complex disorders. The development of the molecular basis of inherited endocrine diseases has undergone a dramatic evolution during the last two decades. The application of molecular technology allowed us to increase our understanding of endocrine diseases, and to impact on the practice of pediatric endocrinology related to diagnosis and genetic counseling. Identification of the mutation in the particular disease by genetic testing leads to precise diagnosis in the equivocal cases and prenatal diagnosis. However, clinicians should be cautious about determining therapeutic decisions solely on the basis of molecular studies, especially in the area of prenatal diagnosis and termination of pregnancy. This review describes an introduction to molecular basis of various inherited endocrine diseases and diagnosis by genetic testing.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• v.11 no.sup1
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• pp.72-82
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• 2008

Wilson disease (WD) is an autosomal recessive disorder of copper metabolism that results in accumulation of copper primarily in the liver, the brain and the cornea. Mutations in the WD gene, ATP7B cause failure of copper excretion from hepatocyte into bile and a defective synthesis of ceruloplasmin. More than 370 mutations are now recognized, scattering throughout the ATP7B gene. Since WD has protean clinical presentations, awareness of WD in clinical practice is important for the early diagnosis and prevention of accumulated copper toxicity. None of the laboratory parameters alone allows a definite diagnosis of WD. There are numerous pitfalls in the diagnosis of WD. Low serum ceruloplasmin concentrations, increased 24 hour urinary copper excretion, increased hepatic copper concentrations and the presence of Kayser-Fleischer rings in the cornea are major diagnostic points. A combination of any two of these 4 laboratory findings is strong support for a diagnosis of WD. Molecular methods are now being used to aid diagnosis. Molecular genetic testing has confirmed the diagnosis in individuals in whom the diagnosis is not clearly established biochemically and clinically. Siblings should be screened for WD once an index case has been diagnosed. Discrimination of heterozygotes from asymptomatic patients is essential to avoid inappropriate lifelong therapy for heterozygotes. Genetic testing, either by haplotype analysis or by mutation analysis, is the only reliable tool for differentiating heterozygote carriers from affected asymptomatic patients. Currently, genetic testing is of limited value in the primary diagnosis. However, genetic testing will soon play an essential role in diagnosing WD as rapid advancement of biomedical technology will allow more rapid, easier and less expensive mutation detection.

• Clinical and Experimental Pediatrics
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• v.61 no.4
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• pp.101-107
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• 2018

Recent advances in genetics have determined that a number of epilepsy syndromes that occur in the first year of life are associated with genetic etiologies. These syndromes range from benign familial epilepsy syndromes to early-onset epileptic encephalopathies that lead to poor prognoses and severe psychomotor retardation. An early genetic diagnosis can save time and overall cost by reducing the amount of time and resources expended to reach a diagnosis. Furthermore, a genetic diagnosis can provide accurate prognostic information and, in certain cases, enable targeted therapy. Here, several early infantile epilepsy syndromes with strong genetic associations are briefly reviewed, and their genotype-phenotype correlations are summarized. Because the clinical presentations of these disorders frequently overlap and have heterogeneous genetic causes, next-generation sequencing (NGS)-based gene panel testing represents a more powerful diagnostic tool than single gene testing. As genetic information accumulates, genetic testing will likely play an increasingly important role in diagnosing pediatric epilepsy. However, the efforts of clinicians to classify phenotypes in nondiagnosed patients and improve their ability to interpret genetic variants remain important in the NGS era.

• Journal of The Korean Society of Inherited Metabolic disease
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• v.23 no.2
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• pp.1-7
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• 2023

Inherited metabolic disorders (IMD) are a group of disorders involving various metabolic pathways. Genetic diagnosis of IMD has been challenging because of extremely heterogeneous nature and extensive laboratory and/or phenotype overlap. Conventional genetic diagnosis was a gene-by-gene approach that needs a priori information on the causative genes that might underlie the IMD. Recent implementation of next-generation sequencing (NGS) technologies has changed the process of genetic diagnosis from a gene-by-gene approach to simultaneous analysis of targeted genes possibly associated with the IMD using gene panels or using whole exome/genome sequencing (WES/WGS) covering entire human genes. Clinical NGS tests can be a cost-effective approach for the rapid diagnosis of IMD with genetic heterogeneity and are becoming standard diagnostic procedures.

• Childhood Kidney Diseases
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• v.26 no.1
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• pp.40-45
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• 2022

Purpose: Chronic kidney disease (CKD) has various underlying causes in children. Identification of the underlying causes of CKD is important. Genetic causes comprise a significant proportion of pediatric CKD cases. Methods: In this study, we performed whole-exome sequencing (WES) to identify genetic causes of pediatric CKD. From January to June 2021, WES was performed using samples from pediatric patients with CKD of unclear etiology. Results: Genetic causes were investigated using WES in 37 patients (17 males) with pediatric CKD stages 1 (n=5), 2 (n=7), 3 (n=2), 4 (n=2), and 5 (n=21). The underlying diseases were focal segmental glomerulosclerosis (n=9), congenital anomalies of the kidney and urinary tract including reflux nephropathy (n=8), other glomerulopathies (n=7), unknown etiology (n=6), and others (n=7). WES identified genetic causes of CKD in 12 of the 37 patients (32.4%). Genetic defects were discovered in the COL4A4 (n=2), WT1 (n=2), ACTN4, CEP290, COL4A3, CUBN, GATA3, LAMA5, NUP107, and PAX2 genes. WT1 defects were found in patients whose pathologic diagnosis was membranoproliferative glomerulonephritis, and identification of CUBN defects led to discontinuation of immunosuppressive agents. Genetic diagnosis confirmed the clinical diagnosis of hypoparathyroidism, sensorineural deafness, and renal disease; Alport syndrome; and Joubert syndrome in three of the patients with CKD of unknown etiology (COL4A4 [n=2], CUBN [n=1]). Extrarenal symptoms were considered phenotypic presentations of WT1, PAX2, and CEP290 defects. Conclusions: WES provided a genetic diagnosis that confirmed the clinical diagnosis in a significant proportion (32.4%) of patients with pediatric CKD.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.17-17
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• 2005

In this presentation, we will discuss several recent achievements developed in my laboratory for microarray-based diagnosis of human genetic mutations including HNF-1 and BRCA1 mutations. To determine the presence of the genetic mutations in a human sample, we prepared allele-specific oligonucleotide chips from selected mutation sites and generated target probes using a tow-step method for Cy-3 DNA $samples^{1)}$ or in vitro transcription of promoter-tagged PCR products for Cy-3 RNA $samples^{2)}$. Hybridization of the target probes to the chips successfully identified all of the genotypes for the tested sites. For more reliable diagnosis, we also employed single base extension (SBE) reaction and zip-code microarray technique for our strategy. Particularly we developed an efficient PNA zip-code microarray for the detection of $HNF-1{\alpha}$ $mutations^{3)}$. Using multiplex SBE reactions and zip-code strategy, we were able to correctly diagnose several mutation sites in exon 2 of $HNF-1{\alpha}$ with a wild-type and mutant including a MODY3 patient. These works represent successful applications of DNA microarray technology for the diagnosis of human genetic mutations.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3651-3658
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• 2016

Computer-aided diagnosis of breast cancer is an important medical approach. In this research paper, we focus on combining two major methodologies, namely fuzzy base systems and the evolutionary genetic algorithms and on applying them to the Saudi Arabian breast cancer diagnosis database, to aid physicians in obtaining an early-computerized diagnosis and hence prevent the development of cancer through identification and removal or treatment of premalignant abnormalities; early detection can also improve survival and decrease mortality by detecting cancer at an early stage when treatment is more effective. Our hybrid algorithm, the genetic-fuzzy algorithm, has produced optimized systems that attain high classification performance, with simple and readily interpreted rules and with a good degree of confidence.