title: Maternal uniparental disomy of chromosome 20: a novel imprinting disorder of growth failure.
abstract: OBJECTIVE
  Maternal uniparental disomy of chromosome 20 (UPD(20)mat) has been reported in only four patients, three of whom also had mosaicism for complete or partial trisomy of chromosome 20. We sought to evaluate the clinical significance of isolated UPD(20)mat in eight individuals.
  
  
  METHODS
  We evaluated phenotypic and genomic findings of a series of eight new patients with UPD(20)mat.
  
  
  RESULTS
  All eight individuals with UPD(20)mat had intrauterine growth restriction, short stature, and prominent feeding difficulties with failure to thrive. As a common feature, they often required gastric tube feeds. Genomic data in most patients are indicative of UPD as a result of trisomy rescue after meiosis II nondisjunction.
  
  
  CONCLUSIONS
  We describe the first natural history of the disorder and the results of therapeutic interventions, including the frequent requirement of direct gastric feedings only during the first few years of life, and propose that growth hormone supplementation is probably safe and effective for this condition. We suggest that UPD(20)mat can be regarded as a new imprinting disorder and its identification requires specialized molecular testing, which should be performed in patients with early-onset idiopathic isolated growth failure.Genet Med 18 4, 309-315.
authors.affiliation: Division of Genomic Diagnostics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Surabhi
authors.identifier: http://orcid.org/0000-0002-2435-7210
authors.initials: S
authors.lastname: Mulchandani
authors.affiliation: Division of Clinical Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Bhoj
authors.affiliation: Division of Genomic Diagnostics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Minjie
authors.initials: M
authors.lastname: Luo
authors.affiliation: Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, Delaware, USA.
authors.forename: Nina
authors.identifier: http://orcid.org/0000-0002-7440-5938
authors.initials: N
authors.lastname: Powell-Hamilton
authors.affiliation: Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, Delaware, USA.
authors.forename: Kim
authors.initials: K
authors.lastname: Jenny
authors.affiliation: Division of Medical Genetics, Alfred I. duPont Hospital for Children, Wilmington, Delaware, USA.
authors.forename: Karen W
authors.identifier: http://orcid.org/0000-0001-8200-1733
authors.initials: KW
authors.lastname: Gripp
authors.affiliation: Institute of Human Genetics, University Hospital, RWTH Aachen, Aachen, Germany.
authors.forename: Miriam
authors.initials: M
authors.lastname: Elbracht
authors.affiliation: Institute of Human Genetics, University Hospital, RWTH Aachen, Aachen, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Eggermann
authors.affiliation: Peninsula Clinical Genetics Service, Royal Devon and Exeter Hospital, Exeter, UK.
authors.forename: Claire L S
authors.initials: CL
authors.lastname: Turner
authors.affiliation: Wessex Clinical Genetics Service, University Hospital Southampton, Southampton, UK.|Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK.
authors.forename: I Karen
authors.initials: IK
authors.lastname: Temple
authors.affiliation: Human Development and Health, Faculty of Medicine, University of Southampton, Southampton, UK.
authors.forename: Deborah J G
authors.initials: DJ
authors.lastname: Mackay
authors.affiliation: Division of Clinical Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Holly
authors.initials: H
authors.lastname: Dubbs
authors.affiliation: Division of Medical Genetics, Stanford University, Stanford, California, USA.
authors.forename: David A
authors.initials: DA
authors.lastname: Stevenson
authors.affiliation: Division of Medical Genetics, Stanford University, Stanford, California, USA.
authors.forename: Leah
authors.initials: L
authors.lastname: Slattery
authors.affiliation: Division of Clinical Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Elaine H
authors.initials: EH
authors.lastname: Zackai
authors.affiliation: Division of Genomic Diagnostics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Nancy B
authors.initials: NB
authors.lastname: Spinner
authors.affiliation: Division of Clinical Genetics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Ian D
authors.initials: ID
authors.lastname: Krantz
authors.affiliation: Division of Genomic Diagnostics, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA.
authors.forename: Laura K
authors.identifier: http://orcid.org/0000-0003-2330-8158
authors.initials: LK
authors.lastname: Conlin
mesh_terms: D002648:Child; D002675:Child, Preschool; D002890:Chromosomes, Human, Pair 20; D019066:Facies; D005260:Female; D018392:Genomic Imprinting; D005838:Genotype; D006130:Growth Disorders / Q000175:diagnosis* / Q000188:drug therapy / Q000235:genetics*; D019382:Human Growth Hormone / Q000172:deficiency / Q000627:therapeutic use; D006801:Humans; D007223:Infant; D008297:Male; D018895:Microsatellite Repeats; D009030:Mosaicism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D024182:Uniparental Disomy / Q000175:diagnosis* / Q000235:genetics*
chemical_list: D019382:Human Growth Hormone