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6th ESACP Congress, Heidelberg, April 7-11, 1999 |
A086
The neighborhood relationships of chromosomes can be of great importance for
basic cellular processes such as gene expression or translocation induction.
In this study, the topological organization of chromosome domains was
investigated in cell nuclei of human blood cells (mostly in Go-lymphocytes).
We found that the domains were predominantly located in particular regions of
cell nuclei. In addition to this, the domains can be probably associated in
pairs. Both effects might substantially increase the probability of
interaction between chromosomes. Because of this, exchange aberrations were
studied in different chromosome pairs in human lymphocytes irradiated by
neutrons. The rate of aberration induction between these chromosomes was
compared with the expected frequency based on the fractional molecular weight
of the chromosomes. An attempt was made to explain the increased rate of
exchanges between some chromosome pairs using the topological parameters of
the chromosomes. Similar topological characteristics of several genes were
found in various human blood cell types: T- and B-lymphocytes, HL60 cells and
bone-marrow cells. This finding suggests that the specific chromatin
structure which is responsible for the increased frequency of the induction
of translocations by ionizing radiation might be also responsible for the
high rate of the induction of leukemias and lymphomas in the human population.
THE ROLE OF THE DISTRIBUTIONS OF CHROMOSOME DOMAINS IN CELL NUCLEI IN THE
INDUCTION OF TRANSLOCATIONS BY IONIZINIG RADIATION AND IN THE PATHOGENESIS
OF LEUKEMIAS AND LYMPHOMAS
Kozubek S, Lukasova E, Skalnikova M, Kozubek M, Bartova E, Jirsova P,
Cafourkova A, Koutna I
Institute of Biophysics, Academy of Sciences, Brno and Faculty of
Informatics, Masaryk University, Brno, Czech Republic