• Journal of Genetic Medicine
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• 제15권2호
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• pp.87-91
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• 2018

X-linked dominant mutations in lysosome-associated membrane protein 2 (LAMP2) gene have been shown to be the cause of Danon disease, which is a rare disease associated with clinical triad of cardiomyopathy, skeletal myopathy, and mental retardation. Cardiac involvement is a common manifestation and is the leading cause of death in Danon disease. We report a case of a 24-month-old boy with hemizygous LAMP2 mutation who presented with failure to thrive and early-onset hypertrophic cardiomyopathy. We applied targeted exome sequencing and found a novel hemizygous c.692del variant in exon 5 of the LAMP2 gene, resulting a frameshift mutation p.Thr231Ilefs*11. Our study indicates that target next-generation sequencing can be used as a fast and highly sensitive screening method for inherited cardiomyopathy.

• Genomics & Informatics
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• 제16권4호
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• pp.35.1-35.3
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• 2018

Biliary tract cancer (BTC) is a rare cancer and is associated with a poor prognosis. To understand the genetic characteristics of BTC, we analyzed whole-exome sequencing data and identified somatic mutations in patients with BTC. Tumors and matched blood or normal samples were obtained from seven patients with cholangiocarcinoma who underwent surgical resection. We discovered inactivating mutations of tumor suppressor genes, including APC, TP53, and ARID1A, in three patients. Activating mutations of KRAS and NRAS were also identified. Our analyses identified somatic mutations in Korean patients with BTC.

• 대한소아신경학회지
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• 제26권4호
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• pp.272-275
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• 2018

KBG 증후군은 특징적인 얼굴 기형 및 발달 장애, 저 신장 등을 보이는 희귀한 질환이며, ANKRD11유전자의 변이가 KBG 증후군을 일으킨다고 알려져 있다. 그 임상 양상의 스펙트럼은 넓은 편이며, 발달 장애와 신경학적 이상의 경우 개인마다 다양한 정도로 보고되고 있다. 본 증례의 환자들 역시 서로 다른 정도의 발달 장애를 보였으며, 그 중 더 심한 정도의 발달 장애를 가진 환자에서는 뇌전증이 동반되었다. 기존의 KBG증후군의 진단 기준에서 macrodontia는 매우 중요한 요소였으며, 대부분의 KBG 증후군 환자에서 나타난다고 보고되었다. 본 증례의 환자들은 발달장애를 보여 시행한 diagnostic exome sequencing을 통해 ANKRD11 유전자 이상을 확인하였지만 macrodontia는 관찰되지 않았다. 이는 KBG 증후군이 현재까지 밝혀진 것 보다 더 흔할 수 있으며, 특징적인 얼굴 기형이 없는 경우에도 발달장애가 있는 환자들에서는 더욱 적극적인 유전자 검사를 시행하여 KBG 증후군을 진단 할 필요가 있음을 시사한다.

• 대한유전성대사질환학회지
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• 제20권2호
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• pp.50-54
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• 2020

Vici 증후군은 18q12.3 염색체에 위치하는 EPG5 유전자의 돌연변이로 인해 발생하는 상 염색체 열성 증후군이다. EPG5 유전자는 리소좀 형성에 관여하는 자가 포식 경로의 중요한 조절자를 암호화하므로 이에 대한 돌연변이로 인해 다양한 임상증상을 나타나게 된다. 주요한 임상증상으로는 뇌량 무형성, 백색증, 백내장, 심근 병증, 중증 정신 운동 지체, 발작, 면역 결핍 등이 있으며 다양한 임상증상을 나타내는 만큼 다른 질환들과 임상적으로 구분하기가 어렵다. 저자들은 Vici 증후군으로 진단된 3세 남자 환아의 증례를 보고하고자 한다. 환아는 생후 2개월 경 근긴장 저하와 수유 곤란을 주소로 내원하였으며 이후 Vici 증후군에서 나타나는 특징적인 임상 증상들을 나타내었다. 임상증상들의 감별 진단을 위해 시행한 Whole-exome sequencing (WES) 결과, EPG5 유전자에서 c.2254 C>T (p.Gln752Ter)와 c.5511-5518+2 del TATGCAAAGT 새로운 변이가 이형접합체로 확인되었다. Vici 증후군과 같이 임상적으로 구분이 어려우며 다양한 신체기관에 걸쳐 영향을 미치는 질환의 진단 시에는 Whole-exome sequencing (WES)가 유용하게 사용될 수 있다. 이 증례는 한국에서 확인된 첫 Vici 증후군 case로써 의의가 있다.

• 대한예방한의학회지
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• 제27권2호
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• pp.35-48
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• 2023

Objective : We studied prognostic biomarkers discovery for lung cancer based on the pattern identification for the personalized Korean medicine. Methods : Using 30 tissue samples, we performed a whole exome sequencing to examine the genetic differences among three groups. Results : The exome sequencing identified among 23,490 SNPs germline variants, 12 variants showed significant frequency differences between Xu and Stasis groups (P<0.0005). As similar, 18 and 10 variants were identified in analysis for Xu vs. Gentleness group and Stasis vs. Gentleness group, respectively (P<0.001). Our exome sequencing also found 8,792 lung cancer specific variants and among the groups identified 6, 34, and 12 variants which showed significant allele frequency differences in the comparison groups; Xu vs. Stasis, Xu vs. Gentleness group, and Stasis vs. Gentleness group. As a result of PCA analysis, in germline data set, Xu group was divided from other groups. Analysis using somatic variants also showed similar result. And in gene ontology analysis using pattern identification variants, we found genes like as FUT3, MYCBPAP, and ST5 were related to tumorigenicity, and tumor metastasis in comparison between Xu and Stasis. Other significant SNPs for two were responsible for eye morphogenesis and olfactory receptor activity. Classification of somatic pattern identification variants showed close relationship in multicellular organism reproduction, anion-anion antiporter activity, and GTPase regulator activity. Conclusions : Taken together, our study identified 40 variants in 29 genes in association with germline difference of pattern identification groups and 52 variants in 47 genes in somatic cancer tissues.

• Clinical and Experimental Pediatrics
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• 제58권9호
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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.

• Pediatric Gastroenterology, Hepatology & Nutrition
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• 제22권6호
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• pp.581-587
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• 2019

Arthrogryposis-renal dysfunction-cholestasis (ARC) syndrome is a rare autosomal recessive multisystemic disease that is associated with the liver, kidney, skin, and central nervous and musculoskeletal systems. ARC occurs as a result of mutations in the VPS33B (Vacuolar protein sorting 33 homolog B) or VIPAR (VPS33B interacting protein, apical-basolateral polarity regulator) genes. A female infant presented with neonatal cholestasis with a severe clinical outcome. She was diagnosed with ARC syndrome using targeted exome sequencing (TES). Exome sequencing revealed compound heterozygous mutations, c.707A>T and c.239+5G>A, in VPS33B, where c.707A>T was a novel variant; the resultant functional protein defects were predicted via in silico analysis. c.239+5G>A, a pathogenic mutation that affects splicing, is found in less than 0.1% of the general population. Invasive techniques, such as liver biopsies, did not contribute to a differential diagnosis of ARC syndrome; thus, early TES together with clinical presentations constituted an apparently accurate diagnostic procedure.

• Journal of Genetic Medicine
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• 제20권2호
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• pp.31-38
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• 2023

Rare diseases, even though defined as fewer than 20,000 in South Korea, with over 8,000 rare Mendelian disorders having been identified, they collectively impact 6-8% of the global population. Many of the rare diseases pose significant challenges to patients, patients' families, and the healthcare system. The diagnostic journey for rare disease patients is often lengthy and arduous, hampered by the genetic diversity and phenotypic complexity of these conditions. With the advent of next-generation sequencing technology and clinical implementation of exome sequencing (ES) and genome sequencing (GS), the diagnostic rate for rare diseases is 25-50% depending on the disease category. It is also allowing more rapid new gene-disease association discovery and equipping us to practice precision medicine by offering tailored medical management plans, early intervention, family planning options. However, a substantial number of patients remain undiagnosed, and it could be due to several factors. Some may not have genetic disorders. Some may have disease-causing variants that are not detectable or interpretable by ES and GS. It's also possible that some patient might have a disease-causing variant in a gene that hasn't yet been linked to a disease. For patients who remain undiagnosed, reanalysis of existing data has shown promises in providing new molecular diagnoses achieved by new gene-disease associations, new variant discovery, and variant reclassification, leading to a 5-10% increase in the diagnostic rate. More advanced approach such as long-read sequencing, transcriptome sequencing and integration of multi-omics data may provide potential values in uncovering elusive genetic causes.

• Korean Journal of Radiology
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• 제23권5호
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• pp.566-567
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• 2022

• Annals of Pediatric Endocrinology and Metabolism
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• 제23권4호
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• pp.169-175
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• 2018

Thyroid dyshormonogenesis is characterized by impairment in one of the several stages of thyroid hormone synthesis and accounts for 10%-15% of congenital hypothyroidism (CH). Seven genes are known to be associated with thyroid dyshormonogenesis: SLC5A5 (NIS), SCL26A4 (PDS), TG, TPO, DUOX2, DUOXA2, and IYD (DHEAL1). Depending on the underlying mechanism, CH can be permanent or transient. Inheritance is usually autosomal recessive, but there are also cases of autosomal dominant inheritance. In this review, we describe the molecular basis, clinical presentation, and genetic diagnosis of CH due to thyroid dyshormonogenesis, with an emphasis on the benefits of targeted exome sequencing as an updated diagnostic approach.