Fig. 2.

Trex2^H188A cells exhibit chromosome DSBs and fragments. Chromosomes are stained with DAPI (blue), a telomeric probe (green) and a MSR probe from the pericentromere (red). In mice the short arms are very small causing the telomeric and MSR probes to overlap resulting in a bleached yellow dot. (A) Metaphase spread with a chromosome DSB/fragment (arrow). (B) Enlargement of the chromosome with a DSB. Note the DSB occurs at the junction of the long arms and the pericentromere such that some of the pericentromere is still attached to the long arms. (C) Graph that shows the Trex2^H188A cells exhibit a greater number of chromosome DSBs compared to AB2.2, trex2^null, Trex2^hTX2 and Trex2^R167A cells. The numbers for both clones shown in Table 1 is averaged.