Stringency washes were done in agitation using a solution of
50% formamide prepared in 2X SSC and 0.1X SSC for 3×5min each
at room temperature. Blocking was performed at 35 ◦C for 30 min
using 5% bovine albumin solution prepared in 4X SSC/0.2% Tween
20. The biotin-labelled probe was detected using fluorescein avidin
and biotinilated antiavidin antibodies (Vector). The slides were
stained with propidium iodide (0.07g/mL) in 2xSSC for 8min and,
once washed and dried, mounted with Vectashield medium (Vector).
All experiments were carried out in dark conditions to prevent
additional DNA damage by natural light.