Comparative Genome Hybridization between Candida albicans and Candida dubliniensis and their derivatives

Total genomic DNAs of J118, CdUM4b, the pseudotetraploid hybrid strain HBT1 and the progeny hybrid strain HBP1 were isolated. In an attempt to determine the number of copies of individual chromosomes, we used comparative genome hybridization (CGH) analysis using specially designed whole genome microarrays representing C. albicans and C. dubliniensis genomes. The arrays contained 60 mer probes that fell in three categories either C. albicans specific or C. dubliniensis specific or common to both. The specific probes were expected to work as internal controls when hybridized to parental genomic DNA alone. The arrays were individually hybridized to Cy3-labeled genomic DNA from either of C. albicans (J118), C. dubliniensis (CdUM4b) parents or the somatic psudotetraploid hybrid strain, HBT1 and the pseudodiploid progeny hybrid HBP1. After experimentally determining species-specific probes and common probes, the ratios of intensity on the HBT1 hybrid array to those of either of the parents were calculated. The copy number was determined for the entire chromosomes by comparing individual probe intensities from the pseudotetraploid to either diploid parent genome DNA intensities. Agilent one-color CGH experiment,Organism: Human ,Agilent-24598 Genotypic designed C.albicans and C. dubliniensis Cross Species CGH Microarray 4x180k , Labeling kit: Agilent Genomic DNA labeling Kit (Part Number: 5190-0453)