Figure 3

FISH characterization of sSMC(2) and sSMC(18) of patient 15 (A-D), and sSMC(22) of patient 18 (E, F). (A) Partial metaphase hybridized with the BAC probe RP11-749K13 at 18p11.21 (red), showing a hybridization signal on idic(18;18) marker chromosomes (white arrow) that is enlarged relative to those on chromosome 18 homologs, as well as cross-hybridization signals on the der(2) marker chromosome (green arrow) and chromosome 2 homologs. The BAC probe RP11-1069D4 at 2p11.1 (blue) produces hybridization signals on der(2) marker chromosome (green arrow) and chromosome 2 homologs. (B) Partial metaphase hybridized with the BAC probe RP11-1035O2 at 18q11.1 does not show a hybridization signal on idic(18;18) (white arrow). (C) Partial metaphase hybridized with the BAC probe RP11-134N21 at 2q11.1, which is deleted on der(2) (green arrow), showing cross-hybridization signals on both idic(18;18) (white arrow) and chromosome 18 homologs. (D) Partial metaphase hybridized with the BAC probe RP11-71B7 at 2q11.1, showing a hybridization signal on der(2) (green arrow) and on chromosome 2 homologs. (E) Metaphase hybridized with the BAC probes RP11-1053O2 at 22q11.21 shows an equal signal on the idic(22;22) marker chromosome (arrow) relative to the signals on the chromosome 22 homologs. (F) Metaphase hybridized with the BAC probe RP11-690P21 at 22q11.21 shows a diminished signal on the idic(22;22) marker chromosome (arrow) relative to the signals on the chromosome 22 homologs.