Restriction digests of the clone give the following sizes (kb): PstI--2.7, 1.6; EcoRI--2.8, 1.5; HindIII--4.3; BamHI--4.3; SacI--4.3. The insert contains an EcoRI site. This is an acrocentric chromosome-specific clone that recognizes a "unique" sequence distal to the ribosome gene cluster on the short arm of all 5 acrocentric chromosomes. It is a subclone of DJ15, a 15 kb BamHI bacteriophage clone containing ribosomal RNA gene sequences, isolated as a junction fragment from the 5' end of the ribosomal gene tandem repeat cluster. Because DJ15 was derived from a total human genomic library, the insert could have been derived from any one of the 5 acrocentrics. ACR-1 is free of ribosomal gene sequences and is specific for the conserved region immediately distal to the rRNA genes on all 5 acrocentric chromosomes. The insert does not hybridize to mouse DNA. |
