title: [Prader-Willi and Angelman syndromes: 21 years of experience].
abstract: BACKGROUND
  Prader-Willi syndrome (PWS) and Angelman syndrome (AS) were the first syndromes in humans that were known to originate from the phenomenon of the genomic imprinting. We review our experience of 21 years with PWS and AS that were confirmed with the genetically.
  
  
  RESULTS
  Of the 13,875 patients recorded during the study period, 11 were diagnosed with PWS (18%), 7 males (63.6%) and 4 females (36.4%), with a mean age of 9.06 years (+/- 6.92, range: 0.68-21.6). The time of the follow up of this group was 3.83 years (+/- 4.03, range: 0.49-15.3), and the age at diagnosis was 4.4 years (+/- 6.84, range: 0.03-19.38). Almost three quarters (72.7% of the PWS patients had a uniparental dysomy and 27.3% a paternal deletion. Six patients (8%) were diagnosed with AS, 4 females (66.6%) and 2 males (33.4%), with a mean age of 14.65 years (+/- 11.89, range: 1.3-30.7). The time of follow up was 6.76 years (+/- 5.89,range: 0.16-15), and the age at diagnosis was 8.84 years (+/- 9.11, range: 1.10-23). A maternal deletion was present in 83.3% of the AS patients and 16.7% had a maternal dysomy.
  
  
  CONCLUSIONS
  As genetic advances are made these pathologies are confirmed before. Unlike the data in the literature, in our series most patients diagnosed with PWS (72'3%) had uniparental disomy. Recent studies correlation genotype with phenotype, in PWS is more serious if it occurs a deletion and in SA is milder in the case of uniparental disomy.
  
  
  CONCLUSIONS
  Genetic studies must be performed in view of the established clinical symptoms: neonatal hypotonia of unknown cause in PWS and psychomotor deficits with autism features, particularly associated with epilepsy, must be evaluated in AS to prevent diagnostic uncertainties, unnecessary complementary examinations and to provide early genetic counselling.
authors.affiliation: Sección Neuropediatría, Hospital Universitario Miguel Servet, Zaragoza, España.
authors.forename: D
authors.initials: D
authors.lastname: Royo Pérez
authors.forename: L
authors.initials: L
authors.lastname: Monge Galindo
authors.forename: J
authors.initials: J
authors.lastname: López Pisón
authors.forename: R
authors.initials: R
authors.lastname: Pérez Delgado
authors.forename: M
authors.initials: M
authors.lastname: Lafuente Hidalgo
authors.forename: J L
authors.initials: JL
authors.lastname: Peña Segura
authors.forename: M D
authors.initials: MD
authors.lastname: Miramar Gallart
authors.forename: A
authors.initials: A
authors.lastname: Rodriguez Valle
authors.forename: M T
authors.initials: MT
authors.lastname: Calvo Martín
mesh_terms: D017204:Angelman Syndrome / Q000175:diagnosis / Q000235:genetics; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D011218:Prader-Willi Syndrome / Q000175:diagnosis / Q000235:genetics; D012189:Retrospective Studies; D013997:Time Factors