Fig. (2) Hybridization of a chromosomal rainbow set comprised of 16 locus-specific probes that map along chromosome 10. A) In metaphase spreads prepared from short term lymphocyte cultures of a healthy donor, the non-rearranged chromosomes 10 showed all 16 signals of the “chromosome rainbow” in the expected order. B) The non-rearranged homologue of chromosome 10 in TPC-1 cells demonstrated the deletion of locus D10S170 (probe 29F6, yellow, indicated by the star). C) The der(21) in TPC-1 carried material from the long arm of chromosome 10 from RET (probe 58C11, purple) to qter. The arrows indicate the characteristic RET-H4/D10S170 (RET/PTC1) inversion. D) Metaphase spreads from our patient carrying the reciprocal t(4;10) showed one normal homologue of chromosome 10 when hybridized with a CR10 set lacking the probe for D10S170 (29F6). E) A der(10) with a breakpoint distal of probe 51H2. F) A der(4) carrying the chromosome 10 material flanked by probes 60D11 and 932F11. G, H) Cell line FTC-236 showed that metaphase spreads contained 2 normal copies of chromosome 10 and a larger marker chromosome (arrow) that carry chromosome 10 material flanked by probes 51H2 and 932F11. Images in A-C were reproduced with kind permission from Springer Verlag, Heidelberg.