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张 钏, 惠 玲, 周 秉, 郑 雷, 王 玉, 郝 胜, 达 振, 马 莹, 郭 金, 曹 宗, 马 旭. [Disease spectrum and pathogenic genes of inherited metabolic disorder in Gansu Province of China]. ZHONGGUO DANG DAI ER KE ZA ZHI = CHINESE JOURNAL OF CONTEMPORARY PEDIATRICS 2024; 26:67-71. [PMID: 38269462 PMCID: PMC10817745 DOI: 10.7499/j.issn.1008-8830.2308094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 08/25/2023] [Accepted: 12/04/2023] [Indexed: 01/26/2024]
Abstract
OBJECTIVES To investigate the disease spectrum and pathogenic genes of inherited metabolic disorder (IMD) among neonates in Gansu Province of China. METHODS A retrospective analysis was conducted on the tandem mass spectrometry data of 286 682 neonates who received IMD screening in Gansu Provincial Maternal and Child Health Hospital from January 2018 to December 2021. A genetic analysis was conducted on the neonates with positive results in tandem mass spectrometry during primary screening and reexamination. RESULTS A total of 23 types of IMD caused by 28 pathogenic genes were found in the 286 682 neonates, and the overall prevalence rate of IMD was 0.63 (1/1 593), among which phenylketonuria showed the highest prevalence rate of 0.32 (1/3 083), followed by methylmalonic acidemia (0.11, 1/8 959) and tetrahydrobiopterin deficiency (0.06, 1/15 927). In this study, 166 variants were identified in the 28 pathogenic genes, with 13 novel variants found in 9 genes. According to American College of Medical Genetics and Genomics guidelines, 5 novel variants were classified as pathogenic variants, 7 were classified as likely pathogenic variants, and 1 was classified as the variant of uncertain significance. CONCLUSIONS This study enriches the database of pathogenic gene variants for IMD and provides basic data for establishing an accurate screening and diagnosis system for IMD in this region.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - 宗富 曹
- 国家卫生健康委科学技术研究所/国家人类遗传资源中心北京100081
| | - 旭 马
- 国家卫生健康委科学技术研究所/国家人类遗传资源中心北京100081
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Chen T, Lu D, Xu F, Ji W, Zhan X, Gao X, Qiu W, Zhang H, Liang L, Gu X, Han L. Newborn screening of maple syrup urine disease and the effect of early diagnosis. Clin Chim Acta 2023; 548:117483. [PMID: 37421976 DOI: 10.1016/j.cca.2023.117483] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2022] [Revised: 07/03/2023] [Accepted: 07/05/2023] [Indexed: 07/10/2023]
Abstract
BACKGROUND Maple syrup urine disease (MSUD) is a rare disease for which newborn screening (NBS) is feasible but not universally applied in China. We shared our experiences with MSUD NBS. METHODS Tandem mass spectrometry-based NBS for MSUD was implemented in January 2003, and diagnostic methods included urine organic acid analysis via gas chromatography-mass spectrometry and genetic analysis. RESULTS Six MSUD patients were identified from 1.3 million newborns, yielding an incidence of 1:219,472, in Shanghai, China. The areas under the curve (AUCs) of total leucine (Xle), Xle/phenylalanine ratio, and Xle/alanine ratio were all 1.000. Some amino acid and acylcarnitine concentrations were markedly low in MSUD patients. 47 MSUD patients identified here and in other centers were investigated, which included 14 patients identified by NBS and 33 patients diagnosed clinically. Forty-four patients were subclassified into classic (n = 29), intermediate (n = 11) and intermittent (n = 4) subtypes. Due to earlier diagnosis and treatment, screened classic patients showed a higher survival rate (62.5%, 5/8) than clinically diagnosed classic patients (5.2%, 1/19). Overall, 56.8% (25/44) of MSUD patients and 77.8% (21/27) of classic patients carried variants in the BCKDHB gene. Among 61 identified genetic variants, 16 novel variants were identified. CONCLUSION MSUD NBS in Shanghai, China, enabled earlier detection and increased survivorship in the screened population.
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Affiliation(s)
- Ting Chen
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Deyun Lu
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Feng Xu
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Wenjun Ji
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Xia Zhan
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Xiaolan Gao
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Wenjuan Qiu
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Huiwen Zhang
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Lili Liang
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Xuefan Gu
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China
| | - Lianshu Han
- Department of Pediatric Endocrinology and Genetic Metabolism, Shanghai Institute for Pediatric Research, Xinhua Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200092, China.
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Li L, Mao X, Yang N, Ji T, Wang S, Ma Y, Yang H, Sang Y, Zhao J, Gong L, Tang Y, Kong Y. Identification of gene mutations in six Chinese patients with maple syrup urine disease. Front Genet 2023; 14:1132364. [PMID: 36911408 PMCID: PMC10001893 DOI: 10.3389/fgene.2023.1132364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Accepted: 02/13/2023] [Indexed: 02/26/2023] Open
Abstract
Background: Maple syrup urine disease (MSUD) is a rare autosomal recessive amino acid metabolic disease. This study is to identify the pathogenic genetic factors of six cases of MUSD and evaluates the application value of high-throughput sequencing technology in the early diagnosis of MUSD. Methods: Clinical examination was carried out for patients and used blood tandem mass spectrometry (MS/MS), urine gas chromatography-mass spectrometry (GC/MS), and the application of high-throughput sequencing technology for detection. Validate candidate mutations by polymerase chain reaction (PCR)-Sanger sequencing technology. Bioinformatics software analyzed the variants' pathogenicity. Using Swiss PDB Viewer software to predict the effect of mutation on the structure of BCKDHA and BCKDHB proteins. Result: A total of six MSUD patients were diagnosed, including four males and two females. Nine variants were found in three genes of six MSUD families by high-throughput sequencing, including four missense mutations: c.659C>T(p.A220V), c.818C>T(p.T273I), c.1134C>G(p.D378E), and c.1006G>A(p.G336S); two non-sense mutations: c.1291C>T(p.R431*) and c.331C>T(p.R111*); three deletion mutations: c.550delT (p.S184Pfs*46), c.718delC (p.P240Lfs*14), and c.795delG (p.N266Tfs*64). Sanger sequencing's results were consistent with the high-throughput sequencing. The bioinformatics software revealed that the mutations were harmful, and the prediction results of Swiss PDB Viewer suggest that variation affects protein conformation. Conclusion: This study identified nine pathogenic variants in the BCKDHA, BCKDHB, and DBT genes in six MSUD families, including two novel pathogenic variants in the BCKDHB gene, which enriched the genetic mutational spectrum of the disease. High-throughput sequencing is essential for the MSUD's differential diagnosis, early treatment, and prenatal diagnosis.
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Affiliation(s)
- Lulu Li
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Xinmei Mao
- Peking University First Hospital Ningxia Women and Children's Hospital (Ningxia Hui Autonomous Region Maternal and Child Health Hospital), Yinchuan, China
| | - Nan Yang
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Taoyun Ji
- Peking University First Hospital Ningxia Women and Children's Hospital (Ningxia Hui Autonomous Region Maternal and Child Health Hospital), Yinchuan, China
| | - Shunan Wang
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Yulan Ma
- Peking University First Hospital Ningxia Women and Children's Hospital (Ningxia Hui Autonomous Region Maternal and Child Health Hospital), Yinchuan, China
| | - Haihe Yang
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Yuting Sang
- Peking University First Hospital Ningxia Women and Children's Hospital (Ningxia Hui Autonomous Region Maternal and Child Health Hospital), Yinchuan, China
| | - Jinqi Zhao
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Lifei Gong
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Yue Tang
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
| | - Yuanyuan Kong
- Department of Newborn Screening Center, Beijing Obstetrics and Gynecology Hospital, Capital Medical University, Beijing Maternal and Child Healthcare Hospital, Beijing, China
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Yıldız Y, Akcan Yıldız L, Dursun A, Tokatlı A, Coşkun T, Tekşam Ö, Sivri HS. Predictors of acute metabolic decompensation in children with maple syrup urine disease at the emergency department. Eur J Pediatr 2020; 179:1107-1114. [PMID: 32048023 DOI: 10.1007/s00431-020-03602-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2019] [Revised: 11/03/2019] [Accepted: 02/02/2020] [Indexed: 12/19/2022]
Abstract
Acute metabolic decompensation (AMD) of maple syrup urine disease (MSUD) must be promptly recognized and treated. In this study, we aimed to identify simple variables associated with AMD in children with MSUD for use in emergency settings. Data were collected retrospectively from 115 emergency visits of 29 children with MSUD over a 4-year period in a major referral hospital. Variables in visits with and without AMD were compared using t test, Mann-Whitney U test, and chi-square test. Logistic regression was used to identify independent variables associated with decompensations. Cut-off values of laboratory variables were determined with receiver operating characteristic curves and correlations with Spearman's rank correlation. Most important variables independently associated with AMD were poor feeding, malaise, anion gap, and especially uric acid, which correlated with leucine levels. Vomiting, dehydration, neurological signs, ketonuria, and ketoaciduria were also associated with AMD. Although sodium, chloride, and glucose were lower in AMD, they had little diagnostic value.Conclusion: In children with MSUD, uric acid and anion gap are key markers for AMD. Poor feeding and malaise are clues before the onset of neurological symptoms. These simple parameters can help determine the presence of AMD in emergency settings.What is Known:• In maple syrup urine disease, acute metabolic decompensations are characterized by gastrointestinal and neurological findings.• Diagnosis requires detection of significantly elevated leucine, which may take a long time or not be available.What is New:• Poor feeding, malaise, hyperuricemia, and high anion gap are parameters that can help diagnose acute decompensations in children with maple syrup urine disease at emergency departments.• Uric acid may be a biomarker for acute decompensations because of its high sensitivity, specificity, and its strong correlation with leucine.
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Affiliation(s)
- Yılmaz Yıldız
- Division of Pediatric Metabolism, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey.
| | - Leman Akcan Yıldız
- Division of Pediatric Emergency, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Ali Dursun
- Division of Pediatric Metabolism, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Ayşegül Tokatlı
- Division of Pediatric Metabolism, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Turgay Coşkun
- Division of Pediatric Metabolism, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Özlem Tekşam
- Division of Pediatric Emergency, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
| | - Hatice Serap Sivri
- Division of Pediatric Metabolism, Department of Pediatrics, Hacettepe University Ihsan Dogramaci Children's Hospital, Ankara, Turkey
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Abstract
Inborn errors of metabolism, also known as inherited metabolic diseases, constitute an important group of conditions presenting with neurologic signs in newborns. They are individually rare but collectively common. Many are treatable through restoration of homeostasis of a disrupted metabolic pathway. Given their frequency and potential for treatment, the clinician should be aware of this group of conditions and learn to identify the typical manifestations of the different inborn errors of metabolism. In this review, we summarize the clinical, laboratory, electrophysiologic, and neuroimaging findings of the different inborn errors of metabolism that can present with florid neurologic signs and symptoms in the neonatal period.
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MESH Headings
- Adult
- Female
- Humans
- Infant, Newborn
- Infant, Newborn, Diseases/diagnosis
- Infant, Newborn, Diseases/diagnostic imaging
- Infant, Newborn, Diseases/physiopathology
- Infant, Newborn, Diseases/therapy
- Metabolism, Inborn Errors/diagnosis
- Metabolism, Inborn Errors/diagnostic imaging
- Metabolism, Inborn Errors/physiopathology
- Metabolism, Inborn Errors/therapy
- Neuroimaging
- Pregnancy
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Affiliation(s)
- Carlos R Ferreira
- Medical Genetics Branch, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, United States; Rare Disease Institute, Children's National Health System, Washington, DC, United States
| | - Clara D M van Karnebeek
- Departments of Pediatrics and Clinical Genetics, Amsterdam University Medical Centers, Amsterdam, The Netherlands; Department of Pediatrics, Centre for Molecular Medicine and Therapeutics, University of British Columbia, Vancouver, BC, Canada.
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Golan Y, Lehvy A, Horev G, Assaraf YG. High proportion of transient neonatal zinc deficiency causing alleles in the general population. J Cell Mol Med 2018; 23:828-840. [PMID: 30450693 PMCID: PMC6349188 DOI: 10.1111/jcmm.13982] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Revised: 09/25/2018] [Accepted: 10/02/2018] [Indexed: 01/01/2023] Open
Abstract
Loss of function (LoF) mutations in the zinc transporter SLC30A2/ZnT2 result in impaired zinc secretion into breast milk consequently causing transient neonatal zinc deficiency (TNZD) in exclusively breastfed infants. However, the frequency of TNZD causing alleles in the general population is yet unknown. Herein, we investigated 115 missense SLC30A2/ZnT2 mutations from the ExAC database, equally distributed in the entire coding region, harboured in 668 alleles in 60 706 healthy individuals of diverse ethnicity. To estimate the frequency of LoF SLC30A2/ZnT2 mutations in the general population, we used bioinformatics tools to predict the potential impact of these mutations on ZnT2 functionality, and corroborated these predictions by a zinc transport assay in human MCF-7 cells. We found 14 missense mutations that were markedly deleterious to zinc transport. Together with two conspicuous LoF mutations in the ExAC database, 26 SLC30A2/ZnT2 alleles harboured deleterious mutations, suggesting that at least 1 in 2334 newborn infants are at risk to develop TNZD. This high frequency of TNZD mutations combined with the World Health Organization-promoted increase in the rate of exclusive breastfeeding highlights the importance of genetic screening for inactivating SLC30A2/ZnT2 mutations in the general population for the early diagnosis and prevention of TNZD.
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Affiliation(s)
- Yarden Golan
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Adrian Lehvy
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
| | - Guy Horev
- Bioinformatics Knowledge Unit, The Lorry I. Lokey Interdisciplinary Center for Life Sciences and Engineering, Technion-Israel Institute of Technology, Haifa, Israel
| | - Yehuda G Assaraf
- The Fred Wyszkowski Cancer Research Laboratory, Department of Biology, Technion-Israel Institute of Technology, Haifa, Israel
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Neuroimaging of Pediatric Metabolic Disorders with Emphasis on Diffusion-Weighted Imaging and MR Spectroscopy: A Pictorial Essay. CURRENT RADIOLOGY REPORTS 2017. [DOI: 10.1007/s40134-017-0251-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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Rousseau-Nepton I, Okubo M, Grabs R, Mitchell J, Polychronakos C, Rodd C. A founder AGL mutation causing glycogen storage disease type IIIa in Inuit identified through whole-exome sequencing: a case series. CMAJ 2015; 187:E68-E73. [PMID: 25602008 DOI: 10.1503/cmaj.140840] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
Abstract
BACKGROUND Glycogen storage disease type III is caused by mutations in both alleles of the AGL gene, which leads to reduced activity of glycogen-debranching enzyme. The clinical picture encompasses hypoglycemia, with glycogen accumulation leading to hepatomegaly and muscle involvement (skeletal and cardiac). We sought to identify the genetic cause of this disease within the Inuit community of Nunavik, in whom previous DNA sequencing had not identified such mutations. METHODS Five Inuit children with a clinical and biochemical diagnosis of glycogen storage disease type IIIa were recruited to undergo genetic testing: 2 underwent whole-exome sequencing and all 5 underwent Sanger sequencing to confirm the identified mutation. Selected DNA regions near the AGL gene were also sequenced to identify a potential founder effect in the community. In addition, control samples from 4 adults of European descent and 7 family members of the affected children were analyzed for the specific mutation by Sanger sequencing. RESULTS We identified a homozygous frame-shift deletion, c.4456delT, in exon 33 of the AGL gene in 2 children by whole-exome sequencing. Confirmation by Sanger sequencing showed the same mutation in all 5 patients, and 5 family members were found to be carriers. With the identification of this mutation in 5 probands, the estimated prevalence of genetically confirmed glycogen storage disease type IIIa in this region is among the highest worldwide (1:2500). Despite identical mutations, we saw variations in clinical features of the disease. INTERPRETATION Our detection of a homozygous frameshift mutation in 5 Inuit children determines the cause of glycogen storage disease type IIIa and confirms a founder effect.
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Affiliation(s)
- Isabelle Rousseau-Nepton
- Department of Pediatrics (Rousseau-Nepton, Mitchell, Polychronakos), Montreal Children's Hospital, Montréal, Que.; Okinaka Memorial Institute for Medical Research (Okubo), Tokyo, Japan; Endocrine Genetics Laboratory (Grabs), Montreal Children's Hospital, McGill University Health Centre, Montréal, Que.; Department of Pediatrics and Child Health (Rodd), Winnipeg, Man
| | - Minoru Okubo
- Department of Pediatrics (Rousseau-Nepton, Mitchell, Polychronakos), Montreal Children's Hospital, Montréal, Que.; Okinaka Memorial Institute for Medical Research (Okubo), Tokyo, Japan; Endocrine Genetics Laboratory (Grabs), Montreal Children's Hospital, McGill University Health Centre, Montréal, Que.; Department of Pediatrics and Child Health (Rodd), Winnipeg, Man
| | - Rosemarie Grabs
- Department of Pediatrics (Rousseau-Nepton, Mitchell, Polychronakos), Montreal Children's Hospital, Montréal, Que.; Okinaka Memorial Institute for Medical Research (Okubo), Tokyo, Japan; Endocrine Genetics Laboratory (Grabs), Montreal Children's Hospital, McGill University Health Centre, Montréal, Que.; Department of Pediatrics and Child Health (Rodd), Winnipeg, Man
| | | | - John Mitchell
- Department of Pediatrics (Rousseau-Nepton, Mitchell, Polychronakos), Montreal Children's Hospital, Montréal, Que.; Okinaka Memorial Institute for Medical Research (Okubo), Tokyo, Japan; Endocrine Genetics Laboratory (Grabs), Montreal Children's Hospital, McGill University Health Centre, Montréal, Que.; Department of Pediatrics and Child Health (Rodd), Winnipeg, Man
| | - Constantin Polychronakos
- Department of Pediatrics (Rousseau-Nepton, Mitchell, Polychronakos), Montreal Children's Hospital, Montréal, Que.; Okinaka Memorial Institute for Medical Research (Okubo), Tokyo, Japan; Endocrine Genetics Laboratory (Grabs), Montreal Children's Hospital, McGill University Health Centre, Montréal, Que.; Department of Pediatrics and Child Health (Rodd), Winnipeg, Man
| | - Celia Rodd
- Department of Pediatrics (Rousseau-Nepton, Mitchell, Polychronakos), Montreal Children's Hospital, Montréal, Que.; Okinaka Memorial Institute for Medical Research (Okubo), Tokyo, Japan; Endocrine Genetics Laboratory (Grabs), Montreal Children's Hospital, McGill University Health Centre, Montréal, Que.; Department of Pediatrics and Child Health (Rodd), Winnipeg, Man.
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