Figure 1: (a) Metaphase spread with the Cytocell PML/RARA extra signal probe showing a fusion signal on one chromosome 15 and a diminished RARA (green) signal on one chromosome 17. (b) Interphase cells with the Vysis dual colour dual fusion probe showing two red and two green signals in the top panel, two red signals in the middle panel, and two green signals plus a tiny third green signal (arrowed) in the bottom panel.