Mosaic paternal uniparental (iso)disomy for chromosome 20 associated with multiple anomalies
Article first published online: 25 JUL 2003
Copyright © 2003 Wiley-Liss, Inc.
American Journal of Medical Genetics Part A
Volume 124A, Issue 3, pages 274–279, 30 January 2004
How to Cite
Venditti, C. P., Hunt, P., Donnenfeld, A., Zackai, E. and Spinner, N. B. (2004), Mosaic paternal uniparental (iso)disomy for chromosome 20 associated with multiple anomalies. Am. J. Med. Genet., 124A: 274–279. doi: 10.1002/ajmg.a.20430
- Issue published online: 31 DEC 2003
- Article first published online: 25 JUL 2003
- Manuscript Accepted: 14 MAY 2003
- Manuscript Received: 29 OCT 2002
- NIDDK. Grant Number: DK53104
- chromosome 20;
- trisomy 20 mosaicism;
- Hirschsprung disease
Uniparental disomy for a number of human chromosomes is associated with clinical abnormalities. We report a child with a complex chromosomal rearrangement involving chromosome 20 (45,XY,psu dic (20;20)(p13;p13)) and paternal uniparental isodisomy for chromosome 20 in peripheral blood and bone marrow. This patient had multiple congenital abnormalities including microtia/anotia, micrencephaly, congenital heart disease, neuronal subependymal heterotopias, and colonic agangliosis. Molecular studies on DNA from peripheral blood demonstrated paternal uniparental inheritance of chromosome 20. However, fibroblasts demonstrated a mosaic karyotype, with one cell line having 45 chromosomes, including the pseudodicentric chromosome 20 (75% of cells), and a second cell line having 46 chromosomes, including the pseudodicentric chromosome 20, and a normal chromosome 20 (trisomy 20) (25% of cells). FISH experiments using a sub-telomeric probe that maps ∼120 kb from the 20p telomere, showed that both copies of these sequences were present on the rearranged chromosome, consistent with deletion of a very small interval. This leads us to suggest that in addition to trisomy 20 mosaicism, paternal uniparental disomy for chromosome 20 could contribute to his clinical phenotype. © 2003 Wiley-Liss, Inc.