A pool of 5,896 haploid-convertible heterozygous diploid yeast knockout (YKO) strains were transformed with a ura3D::URA3 (as target source1) or a tub1D::URA3 (as target source2) cassette. The two Pools of diploid YKOs were harvested after incubation at 30 degree for 2 days on SC-Ura medium. Genomic DNA samples were prepared from these two pools and used as the templates for PCR amplification of the TAGs identifying the YKOs with a pair of primers universal for either Uptags or Downtags. The PCR products from sample1 were labeled with Cy5 and those from sample2 with Cy3. The Cy5- and Cy3-labeled Uptags and Downtags were mixed together and hybridized to a Hopkins-TagArray. Fluorescent array images were collected for both Cy5 and Cy3 with a GenePix4000B microarray scanner. The image data was annalyzed with a GenePix5.1 program. Keywords = tub1D, SHI, heterozygotes, YKO