Transposable Elements (Ty) in Yeast

Recent studies on the organization of chromosomal DNA in eukaryotes demonstrate hat the eukaryotic ge-nome contains families of dispersed repetitive DNA se-quences (Finnegan et al. 1978; Cameron et al. 1979). These repeated sequences are s veral kilobase pairs (kbp) in length and differ widely in copy number and position among different strains of the same species. Analysis of chromosomal sequences, before and after insertion of an element, shows that these repetitive se-quences move to new locations in the genome by non-homologous recombination events. The eukaryotic transposons can catalyze a large number of genomic rearrangements, including translocations, deletions, in-versions, and transpositions (McClintock 1957; Chaleff and Fink 1980; Roeder and Fink 1980). The mobility o