YAC vectors Plasmid with Yac vector elements Expose yeast cells to recombinant YACs; a small percentage of YACs Centromere enter yeast cells Origin of Foreign DNA Restriction replication sites Selectable marker 1 Selectable Telomeres marker 2 Partial digestion Cut with several with EcoRI restriction enzymes to release two 8② ector arms Recombinant YACs replicate in yeast cells. 2 Combine vector arms and fragments; ligate with phosphatase 2 2 2 Plate onto medium containing two antibiotics Cells containing YACs with two selectable markers survive