title: Imprinting center analysis in Prader-Willi and Angelman syndrome patients with typical and atypical phenotypes.
abstract: Prader-Willi syndrome (PWS) and Angelman syndrome (AS) are genetic disorders caused by a deficiency of imprinted gene expression from the paternal or maternal chromosome 15, respectively. This deficiency is due to the deletion of the 15q11-q13 region, parental uniparental disomy of the chromosome 15, or imprinting defect (ID). Mutation of the UBE3A gene causes approximately 10% of AS cases. In this present study, we describe the molecular analysis and phenotypes of two PWS patients and four AS patients with ID. One of the PWS patients has a non-familial imprinting center (IC) deletion and displayed a severe phenotype with an atypical PWS appearance, hyperactivity and psychiatric vulnerability. The other PWS and AS patients did not present genetic abnormalities in the IC, suggesting an epimutation as the genetic cause. The methylation pattern of two AS patients showed a faint maternal band corresponding to a mosaic ID. One of these mosaic patients displayed a mild AS phenotype while the other displayed a PWS-like phenotype.
authors.affiliation: Unitat de Biologia Cel-lular, Facultat de Ciències, Universitat Autònoma de Barcelona, Bellaterra, Spain. cristina.camprubi@uab.es
authors.forename: Cristina
authors.initials: C
authors.lastname: Camprubí
authors.forename: Maria Dolors
authors.initials: MD
authors.lastname: Coll
authors.forename: Sergi
authors.initials: S
authors.lastname: Villatoro
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Gabau
authors.forename: Amine
authors.initials: A
authors.lastname: Kamli
authors.forename: Maria Jesus
authors.initials: MJ
authors.lastname: Martínez
authors.forename: David
authors.initials: D
authors.lastname: Poyatos
authors.forename: Miriam
authors.initials: M
authors.lastname: Guitart
mesh_terms: D000328:Adult; D017204:Angelman Syndrome / Q000235:genetics* / Q000473:pathology; D015139:Blotting, Southern; D002648:Child; D002675:Child, Preschool; D019175:DNA Methylation; D005260:Female; D018392:Genomic Imprinting; D006801:Humans; D008297:Male; D009030:Mosaicism; D010641:Phenotype; D016133:Polymerase Chain Reaction; D011218:Prader-Willi Syndrome / Q000235:genetics* / Q000473:pathology