Sequence analysis of the juxtacentromeric region of chromosome 21. Grayscales of the horizontal bar correspond to α-satellites, to regions that are rich in segmental duplications, and to unique sequences (from proximal to distal). Genes and pseudogenes are indicated below the bar. In the upper panel representation of copy numbers of nearly identical sequences in the genome, in black is bioinformatics data complied from http://humanparalogy.gs.washington.edu/eichler/celera5/, with the approximate copy number on the left. Unique sequences are in gray. Hollow bars show the results of PCR on a panel of monochromosomal hybrid DNAs (PCR details on request). Copy number is above each bar. Dotted lines indicate positions of the last two PCR sites that give signals on multiple chromosomes and the first chromosome 21-specific PCR site. The x-axis is in base pairs in contig NT_011512.10/Hs21_11669.
