Examples of FISH analyses of i(17q). YAC and pcp17 probes appear as red signals (Cy3), whereas wcp17 and cen17 probes appear as green signals (FITC). When red (Cy3) and green (FITC) signals are located adjacent to each other a yellow signal is obtained. Chromosomes were counterstained using DAPI, yielding a blue color. (A) Case 1 hybridized with a combination of YAC 935a6 and wcp17 showing the absence of a YAC signal on i(17q) and presence of a signal on the normal chromosome 17. (B) Case 1 hybridized with a combination of pcp17 and cen17 showing two separate centromere 17 signals on the i(17q), with 17p material present in between. (C) Case 7 hybridized with a combination of YAC 935a6 and wcp17 showing a split YAC signal on i(17q), with one signal on each q arm. (D) Case 11 hybridized with a combination of YAC 828b9 and wcp17 showing the presence of a YAC signal on i(17q). (E) Case 11 hybridized with a combination of YAC 481h11 and wcp17 showing the absence of YAC signal on i(17q) and presence of a signal on the normal chromosome 17. (F) Case 19 hybridized with a combination of YAC 961f10 and wcp17 showing the presence of YAC signal on i(17q).