How to cite this article: Iwarsson E, Sahlén S, Nordgren A. 2009. Jumping translocation in a phenotypically normal male: A study of mosaicism in spermatozoa, lymphocytes, and fibroblasts. Am J Med Genet Part A 149A:1706–1711.
Jumping translocation in a phenotypically normal male: A study of mosaicism in spermatozoa, lymphocytes, and fibroblasts†
Article first published online: 16 JUL 2009
Copyright © 2009 Wiley-Liss, Inc.
American Journal of Medical Genetics Part A
Volume 149A, Issue 8, pages 1706–1711, August 2009
How to Cite
Iwarsson, E., Sahlén, S. and Nordgren, A. (2009), Jumping translocation in a phenotypically normal male: A study of mosaicism in spermatozoa, lymphocytes, and fibroblasts. Am. J. Med. Genet., 149A: 1706–1711. doi: 10.1002/ajmg.a.32984
- Issue published online: 23 JUL 2009
- Article first published online: 16 JUL 2009
- Manuscript Accepted: 18 MAY 2009
- Manuscript Received: 10 DEC 2008
- jumping translocation;
- Robertsonian translocation;
- trisomy 13;
Both Robertsonian translocations, rob(13;13) and rob(13;15), (in the present case defined as dic(13;15)), are rare chromosomal rearrangements and there is scarce information regarding their behavior during meiosis. In this report we describe a man with mosaicism for two cell lines, each cell line containing a different de novo Robertsonian translocation with the common breakpoint in the centromeric region on chromosome 13. The karyotype was finally defined as: 45,XY,rob(13;13)(q10;q10)/45,XY,dic(13;15)(p11.2;p12), a phenomenon referred to as jumping translocation. The relative occurrence of the two clones in lymphocytes and fibroblasts as well as the meiotic segregation in spermatozoa and the mechanism of formation were studied using karyotype analysis, fluorescence in situ hybridization (FISH), and quantitative fluorescence-PCR. Karyotype analysis of cultured lymphocytes revealed 57% rob(13;13) cells and 43% dic(13;15) cells and for cultured skin fibroblasts the figures were almost identical (56% and 44%, respectively). FISH analysis showed 55% balanced nuclei for unselected spermatozoa and after swim-up selection the number of balanced spermatozoa decreased to 41%. In addition, 16% of the unselected spermatozoa and 27% of the spermatozoa after swim-up selection carried an additional chromosome 13, indicating a high risk for a trisomy 13 offspring. Swim-up selection did not increase the number of balanced spermatozoa. © 2009 Wiley-Liss, Inc.