Natarajan A T, Boei J J, Vermeulen S, Balajee A S
Department of Radiation Genetics and Chemical Mutagenesis, Leiden University, Netherlands.
Mutat Res. 1996 Nov 11;372(1):1-7. doi: 10.1016/S0027-5107(96)00209-6.
Frequencies of intra-chromosomal exchanges (pericentric inversions and centric rings) and inter-chromosomal exchanges (dicentrics and translocations) in X-irradiated (2.5 Gy) human lymphocytes have been estimated. To detect these events we employed FISH (fluorescence in situ hybridization) technique and arm specific painting probes for chromosomes #1 and #3. The ratio between centric rings and pericentric inversions was found to be about 1. For intra-changes to inter-changes, the ratio (F) was between 6 and 9. Based on the total number of colour junctions involving chromosomes #1 and #3 it was found that exchanges between the arms of the same chromosome occur about 8.7 times more than inter-chromosomal exchanges calculated on the basis of the DNA content of the chromosomes and random induction of aberrations in the total genome. Chromosomal organization in interphase nucleus appears to promote the formation of more intra-changes than inter-changes following X-irradiation, most probably due to close proximity of the two arms of a chromosome.
已估算了经X射线照射（2.5 Gy）的人类淋巴细胞中染色体内部交换（臂间倒位和着丝粒环）及染色体间交换（双着丝粒和易位）的频率。为检测这些事件，我们采用了荧光原位杂交（FISH）技术以及针对1号和3号染色体的臂特异性涂染探针。发现着丝粒环与臂间倒位的比例约为1。对于染色体内部交换与染色体间交换，该比例（F）在6至9之间。基于涉及1号和3号染色体的颜色连接总数发现，同一染色体臂间的交换发生频率比基于染色体DNA含量及全基因组随机诱导畸变计算出的染色体间交换频率高约8.7倍。间期核中的染色体组织似乎在X射线照射后促进了更多的染色体内部交换而非染色体间交换，这很可能是由于一条染色体的两条臂彼此靠近。
