Representative images of radiation-induced chromosomal aberrations. Metaphase spreads hybridized with probes specific for chromosomes 1 (DEAC/blue), 5 (FITC/green), and 11 (Texas Red/red) and chromosomes 3 (DEAC), 7 (FITC), and 21 (Texas Red). Corresponding black-and-white images are also shown (original magnification ×630). (A) Chromosome 1 is involved in a reciprocal translocation (t) with an unpainted chromosome. (B) Chromosome 5 is involved in a dicentric with chromosome 11 accompanied by a dual-color fragment. (C) Break in chromosome 11 resulting in 2 parts: 1 with a centromere (centric fragment) and 1 without a centromere (acentric fragment). (D) Chromosome 11 is involved in a dicentric with an unpainted chromosome accompanied by a fragment. (E) Multiple abnormalities, including insertion of portion of chromosome 7 into chromosome 3 accompanied by dual-color fragment. (F) Chromosome 7 is involved in a terminal translocation with an unpainted chromosome.