sentences:  The goal of transformation-associated recombination (TAR) technology in synthetic genomics is to combine DNA contigs by means of homologous recombination performed by the yeast artificial chromosome (YAC).Of importance is the CEN element within the YAC vector, which corresponds to the yeast centromere.This sequence gives the vector the ability to behave in a chromosomal manner, thereby allowing it to perform homologous recombination.