Segmental maternal heterodisomy of the proximal part of chromosome 15 in an infant with Prader-Willi syndrome

Eur J Hum Genet. 2004 May;12(5):411-4. doi: 10.1038/sj.ejhg.5201168.


Uniparental disomy (UPD) 15, detected in patients with Prader-Willi (PWS) and Angelman syndromes, has to date always involved the entire chromosome 15. We report the first case of segmental maternal uniparental heterodisomy confined to a proximal part of chromosome 15 in a child with clinical features of PWS. This unusual finding can be explained by the rare combination of three consecutive events: a trisomy 15 zygote caused by a maternal meiosis I error, early postzygotic mitotic recombination between maternal and paternal chromatids, and, finally, trisomy rescue by the loss of the rearranged chromosome 15 containing the paternal 15q11-q13 segment.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Autoantigens
  • Child, Preschool
  • Chromosome Mapping
  • Chromosomes, Human, Pair 15 / genetics*
  • Female
  • Humans
  • In Situ Hybridization, Fluorescence
  • Infant
  • Male
  • Microsatellite Repeats
  • Neoplasm Proteins / genetics
  • Nuclear Proteins / genetics
  • Prader-Willi Syndrome / genetics*
  • Prader-Willi Syndrome / pathology
  • Promyelocytic Leukemia Protein
  • Ribonucleoproteins, Small Nuclear / genetics
  • Transcription Factors / genetics
  • Tumor Suppressor Proteins
  • Uniparental Disomy*
  • snRNP Core Proteins


  • Autoantigens
  • Neoplasm Proteins
  • Nuclear Proteins
  • Promyelocytic Leukemia Protein
  • Ribonucleoproteins, Small Nuclear
  • Transcription Factors
  • Tumor Suppressor Proteins
  • snRNP Core Proteins
  • PML protein, human