2p11 vs. 22q11 pericentromeric organization. Miropeat analysis was performed using the 162 kb of 2p11 reference sequence and 600 kb of finished chromosome 22 sequence contig 3. Miropeats identifies regions of sequence similarity and displays this similarity information graphically in the positional context of the sequence (vertical line) as black bars delineated by joining lines between the two sequences (http://www.genome.ou.edu/miropeats.html). Comparisons were performed using repeat-masked versions (RepeatMasker v. 3.0) of the sequences (consequently small breaks in the sequence similarity are indicated). Note the colinearity of duplicons 1 and 2 (see Fig. 3 for a detailed description of duplication content). Duplicon 3 is located 300 kb distal to the first sequence overlap in an inverted orientation. At least two rearrangement events must be invoked to account for this comparative organization. Duplicon 4, although present by monochromosomal hybrid analysis within chromosome 22 (Fig.5a) could not be identified in any of the current finished sequence. This duplicated segment presumably lies within one of the remaining sequence gaps of 22q11.
