Molecular characterization of the breakpoints in rob(13q14q) by fluorescence in situ hybridization
- Baylor College of Medicine, Houston, TX (United States)
- Murdoch Institute, Melbourne (Australia)
Robertsonian translocations are the most common rearrangements in humans with rob(13q14q) contributing to the majority of all ascertained rearrangements. Studying the sequences around the breakpoint regions of Robertsonian translocations may enable us to understand the underlying mechanisms of translocation formation and the molecular organization of the centromeric and pericentromeric regions of the acrocentric chromosomes. We have characterized 17 rob(13q14q), including 6 de novo rearrangements, 5 maternally and 3 paternally inherited rearrangements, and 3 of undetermined origin, by dual color fluorescence in situ hybridization (FISH) and 6 molecular probes which are specific for the repetitive sequences in the centromeric and short arm regions of acrocentric chromosomes. The centromeric alpha satellite DNA probes D21Z1/D13Z1 and D14Z1/D22Z1 showed all rob(13q14q) chromosomes to be dicentric. The rDNA probe did not hybridize to the 17 translocations studied. The pTRS-47 satellite III DNA probe specific for chromosomes 14 and 22 indicated the retention of pTRS-47 sequences around the breakpoints in all cases studied. However, pTRS-63 satellite III probe specific for chromosome 14 did not show any signals on the translocation chromosomes. In 16 of 17 translocations, strong hybridization signals were detected with pTRI-6 satellite I DNA probe specific for chromosome 13. All parental chromosomes 13 and 14 for 6 de novo rob(13q14q), including one whose pTRI-6 sequence was lost, showed strong hybridization signals with pTRS-47 and pTRS-63, and pTRI-6 probes, respectively. These results demonstrate that the breakpoints fall between the pTRS-47 and pTRS-63 sequences in the p11 region of chromosome 14 and between the pTRI-6 and rDNA sequences within the p11 region of chromosome 13 further narrowing the region containing the rob(13q14q) breakpoints.
- OSTI ID:
- 133691
- Report Number(s):
- CONF-941009-; ISSN 0002-9297; TRN: 95:005313-0421
- Journal Information:
- American Journal of Human Genetics, Vol. 55, Issue Suppl.3; Conference: 44. annual meeting of the American Society of Human Genetics, Montreal (Canada), 18-22 Oct 1994; Other Information: PBD: Sep 1994
- Country of Publication:
- United States
- Language:
- English
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