Figure 2.

DJ and PJ acrocentric chromosome conservation. (A) PCR performed at increasing distances (left) into the DJ from mouse somatic cell hybrids carrying a single human acrocentric chromosome (indicated above). The right-hand lanes show PCR performed on the reciprocal products (Xder21 and 21derX) of a chr21 translocation that originates in the rDNA, confirming the DJ is located distally to the rDNA. Bottom panel is the same, but uses primers to the single unique PJ region. (B) Average intrachromosomal and interchromosomal DJ and PJ sequence identities from pairwise comparisons of representative BAC and cosmid clones are plotted.