Fig. 3.
Examples of IR-induced CAs in S-phase 51D1 cells. (A) 150 cGy, elutriation fraction 13 (~75% S); metaphase with chromatid breaks (CB) and inter- and intra-chromosomal chromatid-type exchanges, including a quadriradial (QR) and sister union (SU), marked by smaller arrows. (B) 300 cGy, elutriation fraction 7 (~60% S); metaphase with an inter-chromosomal chromatid-type exchange [triradial (TR), marked by smaller arrow] and complex exchange involving seven chromosomes (marked by larger arrow). (C) 300 cGy, elutriation fraction 10 (~75% S); metaphase with two complex exchanges involving four and five chromosomes (marked by larger arrows).