Both authors contributed equally to this work.
Tissue-specific differences in the proportion of mosaic large NF1 deletions are suggestive of a selective growth advantage of hematopoietic del(+/−) stem cells†
Article first published online: 23 JAN 2012
© 2011 Wiley Periodicals, Inc.
Volume 33, Issue 3, pages 541–550, March 2012
How to Cite
Roehl, A. C., Mussotter, T., Cooper, D. N., Kluwe, L., Wimmer, K., Högel, J., Zetzmann, M., Vogt, J., Mautner, V.-F. and Kehrer-Sawatzki, H. (2012), Tissue-specific differences in the proportion of mosaic large NF1 deletions are suggestive of a selective growth advantage of hematopoietic del(+/−) stem cells. Hum. Mutat., 33: 541–550. doi: 10.1002/humu.22013
Ian N.M. Day
- Issue published online: 14 FEB 2012
- Article first published online: 23 JAN 2012
- Accepted manuscript online: 21 DEC 2011 09:49AM EST
- Manuscript Accepted: 12 DEC 2011
- Manuscript Received: 18 SEP 2011
- DFG (KE 724/9-1; KE 724/7-1); Deutsche Krebshilfe (#108793)
- neurofibromatosis type 1;
- mitotic NAHR
Type-2 NF1 deletions spanning 1.2 Mb are frequently of postzygotic origin and hence tend to be associated with mosaicism for normal cells and those harboring the deletion (del(+/−) cells). Eleven patients with mosaic type-2 deletions were investigated by FISH and high proportions (94–99%) of del(+/−) cells were detected both in whole blood and in isolated CD3+, CD14+, CD15+, and CD19+ leukocytes. Significantly lower proportions of del(+/−) cells (24-82%) were however noted in urine-derived epithelial cells. A patient harboring an atypical large NF1 deletion with nonrecurrent breakpoints was also found to have a much higher proportion of del(+/−) cells in blood (96%) than in urine (51%). The tissue-specific differences in the proportions of del(+/−) cells as well as the X chromosome inactivation (XCI) patterns observed in these mosaic patients suggest that the majority of the deletions had occurred before or during the preimplantation blastocyst stage before the onset of XCI. We postulate that hematopoietic del(+/−) stem cells present at an early developmental stage are characterized by a selective growth advantage over normal cells lacking the deletion, leading to a high proportion of del(+/−) cells in peripheral blood from the affected patients. Hum Mutat 33:541–550, 2012. © 2011 Wiley Periodicals, Inc.