Comparison of gene expression between male and female blastocysts

Male embryos are reported to develop faster than female in the preimplantation stage. Therefore, male and female embryos can be considered phenotypically different as early as the preimplantation stage. Employing our sexing system of enhanced green fluorescent protein (EGFP) tagging X chromosomes, we compared the global gene expression pattern of male and female embryos at the blastocyst stage using DNA microarray. Keywords= sex differentiation Keywords= preimplantation embryo Keywords= genomic imprinting Keywords: comparative hybridization samples were collected from three independent preparations and the experiments were triplicated. Scanned microarray results were processed with Feature Extraction software (ver. 7.5, Agilent). 　The hybridization experiments were duplicated in a reciprocal labeling manner to reduce dye integration bias, and total of six hybridizations were carried out for the entire analysis.　 Combining plural array results and statistical analyses were carried out by Luminator software (Rosetta).