YAC
YAC stands for yeast artificial chromosome, a vector (carrier) created and used in the laboratory to clone pieces of DNA.
A YAC is constructed from the telomeric, centromeric, and replication origin sequences needed for replication in yeast cells.
(The telomere is the end of the chromosome; the centromere is the chromosome region to which spindle fibers attach during cell division; and the replication origin sequences are the spots where the replication of DNA starts.)