ABSTRACT

Artificial chromosomes were first assembled in yeast by combining centromere sequences, a selectable marker, an origin of replication and fl anked by telomeres at the ends (Murray and Szostak 1983). However, the centromeres of yeast are unusual (Malik and Henikoff 2009) in that they are point centromeres in contrast to the repetitive arrays that compose centromeres of multicellular eukaryotes including maize. Artificial chromosomes have been generated in mammalian cells by transformation

Division of Biological Sciences, University of Missouri, Columbia, MO 65211. e-mail: BirchlerJ@Missouri.edu

of large fragments of centromeres and selectable markers, which most often produce large conglomerates (Harrington et al. 1997). Artifi cial chromosomes have also been produced in mammals by the use of telomere mediated chromosomal truncation to cleave the chromosome arms leaving the endogenous centromere for new additions via homologous recombination (Farr et al. 1991, 1992, 1995; Heller et al. 1996).