The authors have nothing to disclose relative to this article.
Genome-wide androgenetic mosaicism
Article first published online: 23 APR 2013
© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd
Volume 85, Issue 3, pages 282–285, March 2014
How to Cite
Johnson, J.P., Waterson, J., Schwanke, C. and Schoof, J. (2014), Genome-wide androgenetic mosaicism. Clinical Genetics, 85: 282–285. doi: 10.1111/cge.12146
- Issue published online: 27 JAN 2014
- Article first published online: 23 APR 2013
- Accepted manuscript online: 19 MAR 2013 08:06AM EST
- Manuscript Revised: 14 MAR 2013
- Manuscript Accepted: 14 MAR 2013
- Manuscript Received: 15 JAN 2013
- Beckwith–Wiedemann syndrome;
- uniparental paternal disomy
Individuals with mosaic paternal uniparental disomy (UPD) of apparently all chromosomes have recently been described. They show a 46,XX karyotype, but with a mixture of normal biparental cells and cells entirely of paternal isodisomic origin. We describe an infant who primarily showed signs of Beckwith–Wiedemann syndrome (BWS), but also had other severe and eventually lethal medical problems, notably refractory hypoglycemia. We performed methylation studies for BWS, but incidentally for Angelman syndrome (AS) on leukocytes and in a skin FFPE sample. We also performed chromosome microarray [CNV and single-nucleotide polymorphism (SNP) array] on leukocytes. We found that the patient had hypomethylation consistent with both BWS and AS. Remarkably, this was due to mosaic paternal UPD for chromosomes 11 and 15, respectively. The SNP microarray showed mosaic paternal UPD for all chromosomes. Patients with unusual phenotypes for a typical imprinting disorder should be studied further with assays for imprinted loci on other chromosomes. Chromosomal SNP microarrays are useful in identifying patients with multiple UPDs, sometimes of the whole genome.