Sex-related transcriptional differences in Day 7 bovine in vitro produced blastocysts

Sexual dimorphism in mammals is mostly attributable to sex-related hormonal differences in fetal and adult tissues; however, this may not be the sole determinant. Though genetically-identical for autosomal chromosomes, male and female preimplantation embryos could display sex-specific transcriptional regulation which can only be attributted to the differences in sexual chromosome dosage. We used microarrays to analyze sex-related transcriptional differences at the blastocyst stage. Day 7 bovine in vitro produced bovine blastocysts produced with sorted semen from 3 different bulls. Pooled RNA from 60 blastocysts of one sex and produced with one bull was used per chip. Three replicates of each sex per bull. In total, 18 Bovine GeneChip (Affymetrix) were used (3 replicates X 3 bulls X 2 sexes).