The sequence of the 3.3-kilobase repetitive element from Dipodomys ordii suggests a mechanism for its amplification and interspersion

Paul S Keim, Karl G. Lark

Research output: Contribution to journalArticle

3 Scopus citations


DNA from the kangaroo rat, Dipodomys ordii, contains a 3.3-kb, highly repeated sequence that is interspersed throughout the genome in small tandem clusters. One 3.3-kb unit has been cloned into pBR322 and the nucleotide sequence determined. The clone used was shown to be representative of the bulk of such sequences found in the genomic DNA. The sequence contains 10 homologous subunits each ca. 260 bp in length. Comparison of these to one another yielded a 258-bp consensus sequence containing a 35-bp terminal inverted repeat. Two unique stretches also occur. One of these contains a region that could serve as a promoter for RNA polymerase III; the other contains a sequence related to the ARS sequences of yeast. It is proposed that an ancestral sequence similar to the consensus sequence was amplified to 10 or more units, and that, subsequently, two other sequences were inserted. The properties of these insertions may have led to the dispersal of the sequence throughout the genome.

Original languageEnglish (US)
Pages (from-to)65-73
Number of pages9
JournalJournal of Molecular Evolution
Issue number1
StatePublished - May 1987
Externally publishedYes



  • Dipodomys ordii
  • DNA amplification
  • DNA interspersion
  • Repetitive DNA

ASJC Scopus subject areas

  • Genetics(clinical)
  • Molecular Biology
  • Genetics
  • Biochemistry
  • Biochemistry, Genetics and Molecular Biology(all)
  • Ecology, Evolution, Behavior and Systematics
  • Agricultural and Biological Sciences (miscellaneous)
  • Agricultural and Biological Sciences(all)

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