Table 1

Frequency of Ura+ cells in haploid strains containing ura3::HIS3 integrated next to a centromere

Chromosome containing ura3::HIS3

Galactose exposure prior to selection

Frequency of Ura+



3.4 ± 3.2 × 10-4



1.0 ± 0.0 × 10-4



9.7 ± 1.8 × 10-5



1.3 ± 0.6 × 10-4

Haploid cells were grown overnight in YPD rich medium. 106 cells were plated onto selective medium lacking uracil. Colonies were counted after 3 days. The mean frequency and standard deviation obtained from at least 4 independent cultures are shown.

a Only 2 independent cultures were tested.

b Cultures were grown in supplemented minimal medium containing raffinose. Where indicated, galactose was added to 1.5% and culture was grown for 1.3 doublings prior to plating onto selective medium. Diluted cultures were also plated to YPD to score viable cell density. Ura+ frequency was computed per viable cell plated. A paired t-test indicates that the frequencies were not different (2-tailed, P > 0.1).

Anders et al. BMC Genetics 2009 10:36   doi:10.1186/1471-2156-10-36

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