title: 47,XYY karyotypes and pervasive developmental disorders.
abstract: OBJECTIVE
  The presence of a 47, XYY karyotype in boys with pervasive developmental disorders (PDDs) has rarely been described in the past. Herein, 2 boys with PDDs and a supernumerary Y chromosome are presented.
  
  
  METHODS
  The case histories of the 2 patients are described along with the results of associated testing. The literature on psychosocial development as well as brain morphology and physiology in males with 47, XYY karyotypes is reviewed.
  
  
  RESULTS
  Both boys had presentations typical of PDDs, one with autistic disorder and the other with PDD not otherwise specified.
  
  
  CONCLUSIONS
  The finding that, in a clinic for children with developmental disorders, 2 of 40 male referrals had 47, XYY karyotypes suggests that the rate of this sex chromosome anomaly may be increased in PDDs. An extra Y chromosome may be related to abnormal brain development, which may, in turn, predispose vulnerable males to PDDs.
authors.affiliation: Department of Psychiatry, University of Toronto, Ontario. nicolson@box-n.nih.gov
authors.forename: R
authors.initials: R
authors.lastname: Nicolson
authors.forename: S
authors.initials: S
authors.lastname: Bhalerao
authors.forename: L
authors.initials: L
authors.lastname: Sloman
mesh_terms: D000293:Adolescent; D001321:Autistic Disorder / Q000235:genetics; D001526:Behavioral Symptoms / Q000235:genetics; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000235:genetics*; D006801:Humans; D008297:Male; D014997:XYY Karyotype / Q000503:physiopathology*