• 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.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 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.

• Korean Journal of Radiology
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• v.22 no.11
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• pp.1858-1874
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• 2021

Recent advances in the molecular and genetic characterization of central nervous system (CNS) tumors have ushered in a new era of tumor classification, diagnosis, and prognostic assessment. In this emerging and rapidly evolving molecular genetic era, imaging plays a critical role in the preoperative diagnosis and surgical planning, molecular marker prediction, targeted treatment planning, and post-therapy assessment of CNS tumors. This review provides an overview of the current imaging methods relevant to the molecular genetic classification of CNS tumors. Specifically, we focused on 1) the correlates between imaging features and specific molecular genetic markers and 2) the post-therapy imaging used for therapeutic assessment.

• Genes and Genomics
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• v.40 no.12
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• pp.1339-1349
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• 2018

Cerebral palsy (CP) is a non-progressive neurological disease, of which susceptibility is linked to genetic and environmental risk factors. More and more studies have shown that CP might be caused by multiple genetic factors, similar to other neurodevelopmental disorders. Due to the high genetic heterogeneity of CP, we focused on investigating related molecular pathways. Ten children with CP were collected for whole-exome sequencing by next-generation sequencing (NGS) technology. Customized processes were used to identify potential pathogenic pathways and variants. Three pathways (axon guidance, transmission across chemical synapses, protein-protein interactions at synapses) with twenty-three genes were identified to be highly correlated with CP. This study showed that the three pathways associated with CP might be the molecular mechanism of pathogenesis. These findings could provide useful clues for developing pathway-based pharmacotherapies. Further studies are required to confirm potential roles for these pathways in the pathogenesis of CP.

• Journal of Genetic Medicine
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• v.17 no.1
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• pp.27-33
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• 2020

Purpose: Duchenne muscular dystrophy (DMD) is the most common lethal muscular dystrophy and is caused by the genetic variants of DMD gene. Because DMD is X-linked recessive and shows familial aggregates, prenatal diagnosis is an important role in the management of DMD family. We present our experience of prenatal molecular diagnosis and carrier detection based on multiplex polymerase chain reaction (PCR), multiplex ligation-dependent probe amplification (MLPA), and linkage analysis. Materials and Methods: During study period, 34 cases of prenatal diagnosis and 21 cases of carrier detection were performed at the Seoul National University Hospital. Multiplex PCR and MLPA was used to detect the exon deletions or duplications. When the DMD pathogenic variant in the affected males is unknown and no DMD pathogenic variant is detected in atrisk females, linkage analysis was used. Results: The prenatal molecular diagnosis was offered to 34 fetuses. Twenty-five fetuses were male and 6 fetuses (24.0%) were affected. Remaining cases had no pathogenic mutation. We had 24 (80.0%) cases of known proband results; exon deletion mutation in 19 (79.2%) cases and duplication in 5 (20.8%) cases. Linkage analysis was performed in 4 cases in which 2 cases (50.0%) were found to be affected. In the carrier testing, among 21 cases including 15 cases of mother and 6 cases of female relative, 9 (42.9%) cases showed positive results and 12 (57.1%) cases showed negative results. Conclusion: Prenatal molecular diagnosis and carrier detection of DMD are effective and feasible. They are useful in genetic counseling for DMD families.

• Journal of Genetic Medicine
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• v.15 no.2
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• pp.64-71
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• 2018

Purpose: Overgrowth syndromes are conditions that involve generalized or localized areas of excess growth. In this study, the clinical, molecular, and genetic characteristics of Korean patients with overgrowth syndrome were analyzed. Materials and Methods: We recruited 13 patients who presented with overgrowth syndrome. All patients fulfilled inclusion criteria of overgrowth syndrome. Analysis of the clinical and molecular investigations of patients with overgrowth syndrome was performed retrospectively. Results: Among the 13 patients with overgrowth syndrome, 9 patients (69.2%) were found to have molecular and genetic causes. Among the seven patients with Sotos syndrome (SS), two had a 5q35microdeletion that was confirmed by fluorescent in situ hybridization. In two patients with SS, intragenic mutations including a novel mutation, c.5993T>A (p.M1998L), were found by Sanger sequencing. One patient had one copy deletion of NDS1 gene which was confirmed by multiplex ligation-dependent probe amplification. Among five patients with Beckwith-Wiedemann syndrome, three had aberrant imprinting control regions; 2 hypermethylation of the differentially methylated region of H19, 1 hypomethylation of the differentially methylated region of Kv. In one patient displaying overlapping clinical features of SS, a de novo heterozygous deletion in the chromosomal region 7q22.1-22.3 was found by single nucleotide polymorphism-based microarray. Conclusion: Considering high detection rate of molecular and genetic abnormalities in this study, rigorous investigations of overgrowth syndrome may be an important tool for the early diagnosis and genetic counseling. A detailed molecular analysis of the rearranged regions may supply the clues for the identification of genes involved in growth regulation.

• 대한생식의학회:학술대회논문집
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• 2000.02a
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• pp.193-202
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• 2000

• Clinical and Experimental Pediatrics
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• v.58 no.9
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• pp.317-324
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• 2015

Kabuki syndrome (KS) is a rare syndrome characterized by multiple congenital anomalies and mental retardation. Other characteristics include a peculiar facial gestalt, short stature, skeletal and visceral abnormalities, cardiac anomalies, and immunological defects. Whole exome sequencing has uncovered the genetic basis of KS. Prior to 2013, there was no molecular genetic information about KS in Korean patients. More recently, direct Sanger sequencing and exome sequencing revealed KMT2D variants in 11 Korean patients and a KDM6A variant in one Korean patient. The high detection rate of KMT2D and KDM6A mutations (92.3%) is expected owing to the strict criteria used to establish a clinical diagnosis. Increased awareness and understanding of KS among clinicians is important for diagnosis and management of KS and for primary care of KS patients. Because mutation detection rates rely on the accuracy of the clinical diagnosis and the inclusion or exclusion of atypical cases, recognition of KS will facilitate the identification of novel mutations. A brief review of KS is provided, highlighting the clinical and genetic characteristics of patients with KS.