title: [X tetrasomy (48,XXXX karyotype) in a girl with altered behavior].
abstract: BACKGROUND
  We report the case of a 14-year-old girl with mental retardation and dysmorphic features referred to child psychiatry because of altered behavior at school.
  
  
  METHODS
  Karyotyping (GTG banding), in situ fluorescent hybridization (FISH) and molecular study of parental origin by polymorphic STS were performed.
  
  
  RESULTS
  Genetic study revealed a 48,XXXX karyotype with a maternal origin of the X-tetrasomy. The mechanism was successive non-dysjunction at meiosis I and II.
  
  
  CONCLUSIONS
  The interest of this case lies in the rarity of the chromosomal anomaly and its late diagnosis, leading to a failure to adapt the girl's education to her needs, with consequences for her psyche.
authors: Unidad de Salud Mental Infanto-Juvenil, Hospital Vega Baja, Orihuela, Alicante, España.
authors: Maria José
authors: MJ
authors: Rodado
authors: Irene
authors: I
authors: Manchón Trives
authors: Belén
authors: B
authors: Lledó Bosch
authors: Francisco
authors: F
authors: Galán Sánchez