<i>Purpose:</i> To investigate the profiles of chromosome damage induced <i>in vitro</i> by exposure to &agr;-particles and &b.gamma;-rays. <i>Materials and methods:</i> Human peripheral blood lymphocytes were exposed to three dose regimes: &agr;-particle doses of 0.2 and 0.5 Gy and a &b.gamma;-ray dose of 1.5 Gy. After culturing for 47 hours, chromosome aberrations involving the number 5 chromosomes were identified using a multi-coloured banding (mBAND) technique. <i>Results:</i> Analysis of the frequencies of chromosome 5 breaks within aberrant cells and within aberrant number 5 chromosomes demonstrated that &agr;-particle irradiation is more likely to result in multiple breaks in a chromosome than &b.gamma;-irradiation. Additionally, overdispersion was observed for all doses for the distribution of breaks amongst all cells analysed and breaks amongst total number 5 chromosomes, with this being greatest for the 0.2 Gy &agr;-particle dose. The ratio of interchanges to intrachanges (F ratio) was 1.4 and 2.4 for 0.2 and 0.5 Gy &agr;-particles respectively and 5.5 for 1.5 Gy &b.gamma;-rays. Evaluation of simple versus complex exchanges indicated ratios of 1.9 and 2.7 for 0.2 and 0.5 Gy &agr;-particles respectively and 10.6 for 1.5 Gy &b.gamma;-rays. The majority of the intrachanges involving chromosomes 5 induced by &agr;-particle radiation were associated with more complex exchanges. <i>Conclusions:</i> This study has confirmed that exchanges induced by exposure to high linear energy transfer (LET) &agr;-particle radiation comprise a greater proportion of intrachanges than those induced by exposure to low LET &b.gamma;-rays. However, since the majority of these are associated with complex rearrangements and likely to be non-transmissible, this limits their applicability as a marker of past <i>in vivo</i> exposure.
Search
Reviews
[Write a review of this article]
Find related articles from these CiteULike users
