Two adolescent patients with coexistent Graves' disease and Moyamoya disease in Korea

Cheon, Chong Kun,Kim, Su Yung,Yoo, Jae-Ho The Korean Pediatric Society 2014 Clinical and Experimental Pediatrics (CEP) Vol.57 No.6

Moyamoya disease is a cerebrovascular condition that results in the narrowing of the vessels of the circle of Willis and collateral vessel formation at the base of the brain. Although relationships between Graves' disease and cerebrovascular accidents in Moyamoya disease are obscure, the coexistence of the two diseases is noteworthy. Moyamoya disease has been rarely reported in adolescent patients with thyrotoxicosis. Recently, we encountered two adolescent Korean patients with Moyamoya disease associated with Graves' disease who presented with episodic right-sided hemiparesis and syncope. These two girls who had Graves' disease had no history of other diseases or head trauma. A thyroid function test revealed a euthyroid state and a high thyroid-stimulating hormone (TSH) receptor antibody titer at that time. The patients were diagnosed with Moyamoya disease based on brain magnetic resonance angiography and cerebral four-vessel angiography. The patients underwent cranial revascularization by encephalo-duroarterio-synangiosis as soon as a diagnosis was made, which resulted in successful symptom resolution. They fared well and had no additional neurological symptoms as of their last follow-up visits. Here, we report these two cases of confirmed Moyamoya disease complicated by Graves' disease with a review of the literature, and discuss the possible association between the two diseases. To our knowledge, this is the first report in South Korea on Moyamoya disease associated with Graves' disease in adolescents with a euthyroid.

Genetic overgrowth syndrome: A single center's experience

Cheon, Chong Kun,Kim, Yoo-Mi,Yoon, Ju Young,Kim, Young A Korean Society of Medical Genetics and Genomics 2018 대한의학유전학회지 Vol.15 No.2

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.

14q32.33 Deletion Identified by array-CGH in a 5-year old-girl with Seizure

Chong Kun Cheon,Sang-Jin Park,Ook Hwan Choi 대한의학유전학회 2011 대한의학유전학회지 Vol.8 No.1

14q32.33을 포함한 14번 염색체 장완 결실은 드문 질환이다. 14번 염색체의 말단 결실은 여러 임상증상을 공통적으로 보일 수 있으나 결실 절단부 (breakpoint)에 따라 표현형이 다양하게 발생할 수 있다. 저자들은 경련을 동반한 5세 여아에서 array comparative genomic hybridization (array-CGH)와 fluorescence in situ hybridization (FISH) 방법을 이용하여 이전 보고에 비해 가장 작은 14q32.33부위의 0.33Mb 크기의 말단 결실과 심하지 않은 표현형을 보이는 1례를 경험 하였기에 문헌고찰과 함께 보고하는 바이다. Deletions of 14q including band 14q32.33 are uncommon. Patients with terminal deletions of chromosome 14 usually share a number of clinical features. By molecular techniques (array comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH), we identified a young girl with 0.3 Mb terminal 14q32.33 deletion. Review of the nine cases with pure terminal 14q32.3 deletions described to date documented that our observation is the smallest terminal 14q deletion ever reported. The phenotype of our patient is much less severe than the phenotypes of the patients reported previously. We report our experience in examining the clinical, behavioral, and cognitive findings in a 5-year-old girl studied with chromosomal microarray hybridization and reviewed previously reported patients with 14q32 deletions.

Considerations for evaluating the effectiveness and longterm outcome of enzyme replacement therapy in Pompe disease

Cheon, Chong Kun The Korean Pediatric Society 2020 Clinical and Experimental Pediatrics (CEP) Vol.63 No.1

Identification of Novel Compound Heterozygous Mutations in the ACADS Gene of an Asymptomatic Korean Newborn with Short Chain Acyl-CoA Dehydrogenase Deficiency by Tandem Mass Spectrometry

Chong Kun Cheon,Hyung Soon Choi,Su-Yung Kim,Han-Wook Yoo,Gu-Hwan Kim 대한의학유전학회 2012 대한의학유전학회지 Vol.9 No.1

Short-chain acyl-CoA dehydrogenase deficiency (SCADD; OMIM # 201470) is an autosomal recessive inborn error of mitochondrial fatty acid β-oxidation, presenting with a variety of clinical signs and symptoms. Developmental delay, hypertonia or hypotonia, ketotic hypoglycemia, and epilepsy are most frequently reported. In general, patients diagnosed through newborn screening have shown normal growth and development in contrast to those diagnosed as a result of clinically initiated evaluations. Here, the case of an asymptomatic Korean newborn with SCADD identified by tandem mass spectrometry is reported. The patient showed an elevated concentration of butyrylcarnitine detected on newborn screening. Urinary excretion of ethylmalonic acid was elevated by urine organic acid analysis. To confirm the diagnosis of SCADD, a direct sequencing analysis of 10 coding exons and the exon-intron boundaries of the ACADS gene were performed. Genetic analysis of ACADS showed the following novel compound heterozygous missense mutations: c.277C>A (p.Leu93Ile) on exon3 and c.682G>A (p.Glu288Lys) on exon6. These results will provide further evidence of mutational heterogeneity for SCADD.

Commentary on "Effects of gonadotropin-releasing hormone agonist treatment on final adult height in boys with idiopathic central precocious puberty"

Cheon Chong Kun 대한소아내분비학회 2021 Annals of Pediatirc Endocrinology & Metabolism Vol.26 No.4

Identification of KMT2D and KDM6A mutations by exome sequencing in Korean patients with Kabuki syndrome.

Cheon, Chong Kun,Sohn, Young Bae,Ko, Jung Min,Lee, Yeoun Joo,Song, Ji Sun,Moon, Jea Woo,Yang, Bo Kyoung,Ha, Il Soo,Bae, Eun Jung,Jin, Hyun-Seok,Jeong, Seon-Yong Springer-Verlag 2014 Journal of human genetics Vol.59 No.6

<P>Kabuki syndrome (KS) (OMIM#147920) is a multiple congenital anomaly/mental retardation syndrome. Recently, pathogenic variants in KMT2D and KDM6A were identified as the causes of KS in 55.8-80.0% of patients. To elucidate further the molecular characteristics of Korean patients with KS, we screened a cohort of patients with clinically defined KS for mutations in KMT2D and KDM6A. Whole-exome sequencing and direct sequencing for validation were performed in 12 patients with a clinical suspicion of KS. KMT2D and KDM6A mutations were identified in 11 (91.7%) patients. No recurrent mutation was observed, and 10 out of the 11 mutations found were novel. KMT2D mutations were detected in 10 patients, including four small deletions or insertions and four nonsense and two missense mutations. One girl had a novel splice-site mutation in KDM6A. Each patient had a unique individual mutation. This is the first report of mutational analysis via exome sequencing in Korean patients with KS. Because the mutation-detection rate was high in this study, rigorous mutation analysis of KMT2D and KDM6A may be an important tool for the early diagnosis and genetic counseling of Korean patients with KS.</P>

14q32.33 Deletion Identified by array-CGH in a 5-year old-girl with Seizure

Cheon, Chong-Kun,Park, Sang-Jin,Choi, Ook-Hwan Korean Society of Medical Genetics and Genomics 2011 대한의학유전학회지 Vol.8 No.1

14q32.33을 포함한 14번 염색체 장완 결실은 드문 질환이다. 14번 염색체의 말단 결실은 여러 임상증상을 공통적으로 보일 수 있으나 결실 절단부 (breakpoint)에 따라 표현형이 다양하게 발생할 수 있다. 저자들은 경련을 동반한 5세 여아에서 array comparative genomic hybridization (array-CGH)와 fluorescence in situ hybridization (FISH) 방법을 이용하여 이전 보고에 비해 가장 작은 14q32.33부위의 0.33 Mb 크기의 말단 결실과 심하지 않은 표현형을 보이는 1례를 경험 하였기에 문헌고찰과 함께 보고하는 바이다. Deletions of 14q including band 14q32.33 are uncommon. Patients with terminal deletions of chromosome 14 usually share a number of clinical features. By molecular techniques (array comparative genomic hybridization (CGH) and fluorescence in situ hybridization (FISH), we identified a young girl with 0.3 Mb terminal 14q32.33 deletion. Review of the nine cases with pure terminal 14q32.3 deletions described to date documented that our observation is the smallest terminal 14q deletion ever reported. The phenotype of our patient is much less severe than the phenotypes of the patients reported previously. We report our experience in examining the clinical, behavioral, and cognitive findings in a 5-year-old girl studied with chromosomal microarray hybridization and reviewed previously reported patients with 14q32 deletions.

Identification of Novel Compound Heterozygous Mutations in the ACADS Gene of an Asymptomatic Korean Newborn with Short Chain Acyl-CoA Dehydrogenase Deficiency by Tandem Mass Spectrometry

Cheon, Chong-Kun,Choi, Hyung-Soon,Kim, Su-Yung,Yoo, Han-Wook,Kim, Gu-Hwan Korean Society of Medical Genetics and Genomics 2012 대한의학유전학회지 Vol.9 No.1

Short-chain acyl-CoA dehydrogenase deficiency (SCADD; OMIM # 201470) is an autosomal recessive inborn error of mitochondrial fatty acid ${\beta}$-oxidation, presenting with a variety of clinical signs and symptoms. Developmental delay, hypertonia or hypotonia, ketotic hypoglycemia, and epilepsy are most frequently reported. In general, patients diagnosed through newborn screening have shown normal growth and development in contrast to those diagnosed as a result of clinically initiated evaluations. Here, the case of an asymptomatic Korean newborn with SCADD identified by tandem mass spectrometry is reported. The patient showed an elevated concentration of butyrylcarnitine detected on newborn screening. Urinary excretion of ethylmalonic acid was elevated by urine organic acid analysis. To confirm the diagnosis of SCADD, a direct sequencing analysis of 10 coding exons and the exon-intron boundaries of the ACADS gene were performed. Genetic analysis of ACADS showed the following novel compound heterozygous missense mutations: c.277C>A (p.Leu93Ile) on exon3 and c.682G>A (p.Glu288Lys) on exon6. These results will provide further evidence of mutational heterogeneity for SCADD.

Kabuki syndrome: clinical and molecular characteristics

Cheon, Chong-Kun,Ko, Jung Min The Korean Pediatric Society 2015 Clinical and Experimental Pediatrics (CEP) Vol.58 No.9

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.