title: Parental reports on early language and motor milestones in fragile X syndrome with and without autism spectrum disorders.
abstract: OBJECTIVE
  This study examined features of early language and motor milestones in children with fragile X syndrome (FXS) and contrasted these features with a diagnosis of Autism Spectrum Disorder (ASD) later in life in these children.
  
  
  METHODS
  We retrospectively examined parental report of age of onset for walking and first words for primarily boys with FXS, both with ASD (FXS + ASD) and FXS-only. The diagnosis of ASD was established by DSM-IV criteria, which were complemented by the ADOS. The age of onset was analyzed as a continuous and categorical variable, which were compared to the upper limit of typically developing children.
  
  
  RESULTS
  Individuals with FXS-only are more delayed in the onset of first words than first walks. The finding represents a pattern suggesting a continuum as robustly demonstrated in individuals with FXS + ASD vs. FXS-only.
  
  
  CONCLUSIONS
  Our results support validity of FXS + ASD co-morbidity as a distinct phenotype in individuals with FXS.
authors.affiliation: Clinical Trials Center, Kennedy Krieger Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Hinton
authors.forename: Dejan B
authors.initials: DB
authors.lastname: Budimirovic
authors.forename: Peter B
authors.initials: PB
authors.lastname: Marschik
authors.forename: Victor B
authors.initials: VB
authors.lastname: Talisa
authors.forename: Christa
authors.initials: C
authors.lastname: Einspieler
authors.forename: Tanjala
authors.initials: T
authors.lastname: Gipson
authors.forename: Michael V
authors.initials: MV
authors.lastname: Johnston
mesh_terms: D002648:Child; D002659:Child Development Disorders, Pervasive / Q000453:epidemiology* / Q000503:physiopathology / Q000534:rehabilitation*; D005260:Female; D005600:Fragile X Syndrome / Q000453:epidemiology* / Q000503:physiopathology / Q000534:rehabilitation*; D006801:Humans; D007804:Language Development; D008297:Male; D010290:Parents; D010641:Phenotype; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D016138:Walking