[Show abstract][Hide abstract] ABSTRACT: CHARGE syndrome (OMIM 214800) is a rare autosomal-dominant congenital malformation syndrome that results from haploinsufficiency of the chromodomain helicase DNA-binding protein 7 (CHD7). We performed a phenotypic characterization and genetic analysis of CHD7 in 18 Korean patients with CHARGE syndrome. Eighteen unrelated Korean patients (10 females and 8 males; age range 0.0-19.6 years) with CHARGE syndrome were enrolled. Clinical data were collected by retrospective review of medical records. A serial analysis via sequencing and multiple ligation-dependent probe amplification of CHD7 was performed to determine the molecular genetic spectrum of the patients. The prevalence of cardinal symptoms was as follows: coloboma (13/18, 72.2%), heart defects (13/18, 72.2%), choanal atresia/stenosis (4/18, 22.2%), retarded growth (10/18, 55.6%), genital anomalies (15/18, 83.3%) and ear abnormalities (18/18, 100%). Five patients had cerebellar vermis hypoplasia (5/17, 29.4%) with no clinical symptoms or signs of cerebellar dysfunction. Furthermore, we identified genetic alterations in all 18 patients, including 10 novel mutations. Considering its frequency among patients with CHD7 mutations, cerebellar vermis hypoplasia may be a clinical diagnostic clue of CHARGE syndrome, although it is not included in the diagnostic critieria. And, the identification of CHD7 mutations may help the confirmative diagnosis.Journal of Human Genetics advance online publication, 5 November 2015; doi:10.1038/jhg.2015.135.
Journal of Human Genetics 11/2015; DOI:10.1038/jhg.2015.135 · 2.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Recent research has demonstrated that genetic alterations or variations contribute considerably to the development of congenital heart disease. Many kinds of genetic tests are commercially available, and more are currently under development. Congenital heart disease is frequently accompanied by genetic syndromes showing both cardiac and extra-cardiac anomalies. Congenital heart disease is the leading cause of birth defects, and is an important cause of morbidity and mortality during infancy and childhood. This review introduces common genetic syndromes showing various types of congenital heart disease, including Down syndrome, Turner syndrome, 22q11 deletion syndrome, Williams syndrome, and Noonan syndrome. Although surgical techniques and perioperative care have improved substantially, patients with genetic syndromes may be at an increased risk of death or major complications associated with surgery. Therefore, risk management based on an accurate genetic diagnosis is necessary in order to effectively plan the surgical and medical management and follow-up for these patients. In addition, multidisciplinary approaches and care for the combined extra-cardiac anomalies may help to reduce mortality and morbidity accompanied with congenital heart disease.
Korean Circulation Journal 09/2015; 45(5):357-61. DOI:10.4070/kcj.2015.45.5.357 · 0.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 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.
Korean Journal of Pediatrics 09/2015; 58(9):317. DOI:10.3345/kjp.2015.58.9.317
[Show abstract][Hide abstract] ABSTRACT: Kabuki syndrome is a multiple congenital malformation syndrome, with characteristic facial features, mental retardation, and skeletal and congenital heart anomalies. However, the cardiac anomalies are not well described in the Korean population. We analyzed the cardiac anomalies and clinical features of Kabuki syndrome in a single tertiary center.
A retrospective analysis was conducted for a total of 13 patients with Kabuki syndrome.
The median age at diagnosis of was 5.9 years (range, 9 days to 11 years and 8 months). All patients showed the characteristic facial dysmorphisms and congenital anomalies in multiple organs, and the diagnosis was delayed by 5.9 years (range, 9 days to 11 years and 5 months) after the first visit. Noncardiac anomalies were found in 84% of patients, and congenital heart diseases were found in 9 patients (69%). All 9 patients exhibited left-side heart anomalies, including hypoplastic left heart syndrome in 3, coarctation of the aorta in 4, aortic valve stenosis in 1, and mitral valve stenosis in 1. None had right-side heart disease or isolated septal defects. Genetic testing in 10 patients revealed 9 novel MLL2 mutations. All 11 patients who were available for follow-up exhibited developmental delays during the median 4 years (range, 9 days to 11 years 11 months) of follow-up. The leading cause of death was hypoplastic left heart syndrome.
Pediatric cardiologist should recognize Kabuki syndrome and the high prevalence of left heart anomalies with Kabuki syndrome. Genetic testing can be helpful for early diagnosis and counseling.
Korean Journal of Pediatrics 07/2015; 58(7):256-62. DOI:10.3345/kjp.2015.58.7.256
[Show abstract][Hide abstract] ABSTRACT: Ornithine transcarbamylase (OTC) deficiency is an X-linked inborn error of the urea cycle that leads to the accumulation of ammonia, resulting in neurological deficits. This study was performed to describe the clinical outcomes, biochemical features and molecular spectra of patients with OTC deficiency. A total of 49 patients from 47 unrelated Korean pedigrees were included who were diagnosed with OTC deficiency based on biochemical findings and molecular analyses. Patient clinical features, biochemical findings and molecular data were analyzed retrospectively. Males with neonatal-onset phenotype presented with seizure or altered mentality (n=20). Biochemical findings showed high blood ammonia (1132.5±851.6 μmol l(-1)) and urine orotic acid (1840.7±1731.3 mmol mol(-1) Cr) levels. There were also five males with late-onset disease who presented with vomiting, irritability and seizure at age 8.2±9.4 years old (range, 0.6-20 years). Symptomatic females presented with vomiting, seizure, and altered mentality at age 3.5±3.5 years (range, 0.2-12.8 years; n=24). More males with the late-onset form and symptomatic females displayed mild hyperammonemia and orotic aciduria compared with those showing a neonatal phenotype (P<0.05). Molecular analysis identified 37 different mutations (22 missense, 5 large deletions, 4 small deletions, 1 insertion, 3 nonsense and 2 splice sites) from all 49 patients; the mutations were dispersed throughout all coding exons. In Korean patients with OTC deficiency, mutations in OTC are genetically heterogeneous. Male patients with the neonatal-onset phenotype showed poor outcomes because of severe hyperammonemia. Early diagnosis and interventions for hyperammonemia can provide more favorable prognosis.Journal of Human Genetics advance online publication, 21 May 2015; doi:10.1038/jhg.2015.54.
Journal of Human Genetics 05/2015; 60(9). DOI:10.1038/jhg.2015.54 · 2.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Gaucher disease is a lysosomal storage disease for which enzyme replacement therapy has proven to be effective. A switch-over clinical trial was performed to evaluate the efficacy and safety of Abcertin® (ISU Abxis, Seoul, Korea) in subjects with type 1 Gaucher disease who were previously treated with imiglucerase. Five Korean patients with type 1 Gaucher disease were enrolled. Previous doses of imiglucerase ranged from 30 to 55 U/kg every other week. The same dose of Abcertin® was administered to all patients for 24 weeks. Primary efficacy endpoints were changes in hemoglobin levels and platelet counts, and the secondary efficacy endpoints included changes in liver and spleen volumes, serum biomarkers, skeletal status and bone mineral density (BMD). During the study period, no statistically significant changes were observed in all parameters including hemoglobin levels and platelet counts, liver and spleen volumes, skeletal status and BMD. Abcertin® administration was continued in three patients for another 24 weeks as an extension of the study. Hemoglobin levels and platelet counts were maintained in all three patients. In conclusion, the efficacy and safety of Abcertin® are similar to those of imiglucerase, and Abcertin® is an effective therapeutic agent for patients with type 1 Gaucher disease (Clinical Trial Registry No. NCT02053896 at www.clinicaltrials.gov).
Journal of Korean medical science 04/2015; 30(4):378-84. DOI:10.3346/jkms.2015.30.4.378 · 1.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Multiple pterygium syndrome (MPS) is an autosomal recessively inherited condition that becomes evident before birth, with pterygium at multiple joints and akinesia. There are two forms of this syndrome that are differentiated by clinical severity: the milder form, Escobar type (OMIM#265000), and the more severe form, lethal type (OMIM#253290). Mutations in CHRNG, which encode the acetylcholine receptor gamma subunit, cause most cases of MPS. Here, we present three patients from two unrelated families showing multiple joint contractures in both the upper and lower limbs. High-arched palates with malocclusion, short neck and micrognathia were observed in all patients. Peripheral blood karyotypes were normal. Whole-exome sequencing analysis of the patients' genomes led to the discovery of identical missense (p.Pro143Arg) and frameshift deletion variants (p.Pro251fs*45) on CHRNG. These were rare cases of congenital arthrogryposis multiplex related to novel recessive CHRNG variants in two Korean kindred without apparent relatedness.Journal of Human Genetics advance online publication, 22 January 2015; doi:10.1038/jhg.2015.2.
Journal of Human Genetics 01/2015; 60(4). DOI:10.1038/jhg.2015.2 · 2.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Neurofibromatosis type 1 (NF1) caused by NF1 gene mutation is a commonly inherited autosomal dominant disorder. Malignant peripheral nerve sheath tumors (MPNSTs), a type of aggressive sarcoma, are a major cause of mortality in NF1 patients. The malignant transformation of benign plexiform neurofibromas (PNs) to MPNSTs is a marked peculiarity in NF1 patients, yet the pathogenesis remains poorly understood. We found that an actin-associated protein transgelin (SM22) was highly expressed in NF1-deficient MPNST tissues compared to NF1-deficient PN tissues using immunohistological staining and primary cultured MPNST cells in western blot analysis. We further found that this transgelin upregulation was caused by increased transcriptional expression of the TAGLN gene encoding transgelin. Comparison of DNA methylation values in the promoter and subpromoter regions of the TAGLN gene in three types of NF1-deficient primary-cultured cells, derived from an NF1 patient's normal phenotype, a benign PN and MPNST tissues, revealed that the TAGLN gene was hypomethylated in the MPNST cells. Next, to determine the functional role of transgelin in MPNST pathogenesis, we manipulated the TAGLN gene expression and investigated the alteration of the RAS-mitogen-activated protein kinase (MAPK) signaling pathway in the normal-phenotypic and malignant tumor cells. The downregulation of TAGLN expression in NF1-deficient MPNST tumor cells through the treatment of the small interfering RNA resulted in a decrease in the RAS activation (GTP-RAS) and the downstream ERK1/2 activation (phosphorylated ERK1/2), while the overexpression of TAGLN in normal-phenotypic NF1-deficient cells caused an increase in RAS and ERK1/2 activation. These results indicate that upregulation of transgelin caused by hypomethylation of the TAGLN gene is closely involved in tumor progression in NF1.
[Show abstract][Hide abstract] ABSTRACT: Kisspeptin/G-protein couple receptor-54 (GPR54) system plays a key role in the activation of the gonadotropic axis at puberty. Central precocious puberty (CPP) is caused by the premature activation of hypothalamic gonadotropin-releasing hormone secretion. This study was aimed to identify KISS1 gene variations and to investigate the associations between KISS1 gene variations and CPP in Korean girls. All coding exons of KISS1 gene were sequenced in Korean girls with CPP (n = 143) and their healthy controls (n = 101). Nine polymorphisms were identified in KISS1 gene. A novel single-nucleotide polymorphism (SNP), 55648176 T/G, was identified for the first time. SNP 55648184 C/G and 55648186 -/T were detected more frequently in CPP group than in control group. SNP 55648176 T/G was detected less frequently in CPP group than in control group. Haplotype GGGC-ACCC was detected less frequently in CPP group. The genetic variations of KISS1 gene can be contributing factors of development of CPP. The association between the gene variations and CPP should be validated by further evidence obtained from large-scaled and functional studies.
Journal of Korean Medical Science 08/2014; 29(8):1120-5. DOI:10.3346/jkms.2014.29.8.1120 · 1.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Arthrogryposis, renal dysfunction, and cholestasis (ARC) syndrome is an autosomal recessive disorder caused by mutations in the VPS33B and VIPAS39. Here, we report novel mutations identified in four patients with ARC syndrome. We analyzed the entire coding regions of the VPS33B and VIPAS39 genes by direct sequencing. To detect novel splice site mutations, mRNA transcripts were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and sequencing. All four patients had compound heterozygous variants in the VPS33B gene. One patient had a previously reported splice site variant with unknown significance, c.239+5G>A, and a novel nonsense mutation, c.621G>A. The other three patients had the c.403+2T>A mutation, and each of them carried one of the splice site variants, c.239+5G>A or c.499−11G>A. c.239+5G>A and c.499−11G>A created novel splice sites which resulted in abnormal transcripts. No significant VIPAS39 mutation was detected in all patients. In patients suspected with ARC syndrome, mutation analysis of the VPS33B gene should be employed as a primary diagnostic test before performing invasive testing procedures such as organ biopsies. Performing mRNA analysis can be useful in predicting the pathogenic phenotype when the mutation seems to affect a normal splicing mechanism.
[Show abstract][Hide abstract] ABSTRACT: The 46,XX testicular disorder of sex development (DSD), also known as 46,XX male syndrome, is a rare form of DSD and clinical phenotype shows complete sex reversal from female to male. The sex-determining region Y (SRY) gene can be identified in most 46,XX testicular DSD patients; however, approximately 20% of patients with 46,XX testicular DSD are SRY-negative. The SRY-box 9 (SOX9) gene has several important functions during testis development and differentiation in males, and overexpression of SOX9 leads to the male development of 46,XX gonads in the absence of SRY. In addition, SOX9 duplication has been found to be a rare cause of 46,XX testicular DSD in humans. Here, we report a 4.2-year-old SRY-negative 46,XX boy with complete sex reversal caused by SOX9 duplication for the first time in Korea. He showed normal external and internal male genitalia except for small testes. Fluorescence in situ hybridization and polymerase chain reaction (PCR) analyses failed to detect the presence of SRY, and SOX9 intragenic mutation was not identified by direct sequencing analysis. Therefore, we performed real-time PCR analyses with specific primer pairs, and duplication of the SOX9 gene was revealed. Although SRY-negative 46,XX testicular DSD is a rare condition, an effort to make an accurate diagnosis is important for the provision of proper genetic counseling and for guiding patients in their long-term management.
[Show abstract][Hide abstract] ABSTRACT: Sotos syndrome (SS) is a congenital overgrowth syndrome. NSD1 mutations are identifiable in most SS patients. There have been a few reports of familial inheritance of SS worldwide, but no familial cases have been reported in Korea. A 6-month-old girl had tall stature and macrocephaly with mild ventricular enlargement, and showed mild delay in motor and language development. Her mother also had tall stature and a long narrow face. The baby and her mother were suspected of having familial SS. Chromosome 5q35 microdeletion was first ruled out by fluorescence in situ hybridization analysis, and direct sequencing of NSD1 revealed a novel heterozygous mutation in exon 22 (c.6356delA; p.Asp2119Valfs*31). This report describes, for the first time, a Korean family with two generations of SS resulting from a novel intragenic NSD1 mutation.
Annals of clinical and laboratory science 05/2014; 44(2):228-31. · 0.91 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: 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.Journal of Human Genetics advance online publication, 17 April 2014; doi:10.1038/jhg.2014.25.
Journal of Human Genetics 04/2014; 59(6). DOI:10.1038/jhg.2014.25 · 2.46 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Unlabelled:
Monochorionic (MC) pregnancy in humans is usually considered to be associated only with monozygotic twinning. However, several reports have revealed that dizygotic (DZ) twins can also share a chorion during pregnancy. A chimera is defined as an organism that contains different cells derived from two or more distinct zygotes. As artificial reproductive techniques develop, it can be predicted that the occurrence of MC DZ twins will increase, and DNA-fingerprinting methods, such as short tandem repeat (STR) analysis, will be essential for their accurate diagnosis. We report the first Korean case of MC DZ twins with blood chimerism, 46,XX/46,XY, as a consequence of in vitro fertilization/embryo transfer. The clinical phenotypes of the twins' genitalia were complete female and male, respectively. Monochorionicity was confirmed by pathological analysis of the placenta after delivery. The dizygosity and confined blood chimerism of the twins were confirmed by STR analysis using their peripheral lymphocytes and skin fibroblasts. The confined blood chimerism of the twins can be considered similar to the status of the hematopoietic system in patients after allogenic bone marrow transplantation.
When MC twins with discordant sex are expected during pregnancy, it is important to consider the possibility of DZ twins showing normal sexual development, especially in twins who were fertilized using artificial reproductive techniques.
European Journal of Pediatrics 04/2014; 173(9). DOI:10.1007/s00431-014-2312-8 · 1.89 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Indium zinc oxide (IZO) thin films were fabricated via self-combustion of In and Zn salts coordinated with fuel and oxidizer ligands. The intense heat generated from the exothermic reaction compensated for the energy required for oxide formation and reduced the temperature required to anneal the oxide films. Thermal analysis of the fuel and oxidizer precursors confirmed the generation of exothermic heat at a relatively low annealing temperature. With the aid of the internal energy that evolved as heat from the combustion reaction, the formation of the metal–oxygen–metal lattice and the removal of organic ligands could be easily accomplished with lower amounts of externally supplied energy. IZO thin-film transistors (TFTs), obtained from this combustive In–Zn pair at a low annealing temperature of 350 C, showed a significantly enhanced field-effect mobility of 13.8 cm 2 V À1 s À1 and a high on/off current ratio of 1.06 Â 10 8 . Inkjet printing of the combustive precursors yielded TFTs with a high field-effect mobility of 5.3 cm 2 V À1 s À1 and an on/off ratio of 10 6 . The high performance, good device uniformity, and high yield of TFTs fabricated by our self-combustion method demonstrate the potential of the proposed system to facilitate the processing of flexible printed electronics.
[Show abstract][Hide abstract] ABSTRACT: Osteogenesis imperfecta (OI) is a group of genetic disorders characterized by bone fragility and connective tissue manifestations. We report a successful liver transplantation (LT) in an 8-month-old boy with OI and cholestatic biliary cirrhosis. After 4 cycles of intravenous pamidronate, LT was performed under intravenous anesthesia using a left lateral section from his mother without mechanical retractors. The operation time was 420 min and estimated blood loss was 520 mL requiring one unit of RBC transfusion. He was discharged without surgical complications. Therefore, LT should be considered for patients with end stage liver disease and OI under organic multidisciplinary cooperation.
Journal of Korean medical science 03/2014; 29(3):441-4. DOI:10.3346/jkms.2014.29.3.441 · 1.27 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose:
Congenital hereditary endothelial dystrophy (CHED) is a rare genetic disorder caused by mutations in corneal endothelial cells. CHED can be divided into 2 types by the modes of inheritance; CHED type 1 (CHED1) with autosomal dominant inheritance and CHED type 2 (CHED2) with autosomal recessive inheritance. Mutations in the sodium bicarbonate transporter-like solute carrier family 4 member 11 (SLC4A11) gene result CHED2.
A 37 years old female was clinically diagnosed as CHED2. Peripheral blood from the patient and her family members was obtained under informed consents. Genomic DNA was extracted in their WBCs, and whole exons and exon-intron boundaries of the SLC4A11 gene were amplified using polymerase chain reaction. The amplified materials were analyzed by direct sequencing method.
The sequencing results of the SLC4A11 gene showed a novel homozygous mutation in exon 9 (c.1158C > A, p.C386*) in the proband with CHED2 phenotype. Her father and sister showing normal cornea were heterozygous carriers of the mutation. Her mother showing late onset Fuchs endothelial corneal dystrophy (FECD) also had the same mutation heterozygously.
We report a novel nonsense mutation of the SLC4A11 gene in the patient with CHED2. In addition, one of heterozygous carriers in this family showed features of late onset FECD. Close clinical ocular examination for the heterozygous carriers should be performed to detect late onset FECD.