Gene expression profile in isolated E13 gonadal somatic support cells and E13 gonads.

Gonadal sex determining (GSD) genes that initiate fetal ovarian and testicular development and differentiation are expressed in the cells of the urogenital ridge that differentiate as somatic support cells (SSCs), i.e., granulosa cells of the ovary and Sertoli cells of the testis. To identify potential new mammalian GSD genes, we analyzed the gene expression differences between XX and XY SSCs cells isolated from the gonads of embryonic day (E) 13 mouse fetuses carrying an EGFP reporter transgene expressed specifically in SSCs. In addition, genome wide expression differences between XX and XY E13 whole gonads were examined. Newly identified differentially expressed transcripts are potential GSD genes involved in unexplained human sex reversal cases. Keywords: microarray, mouse fetal gonadal somatic support cells, sex determination Two seperate RNA samples were obtained from E13 XX and XY sorted EGFP+ cells, and two seperate RNA samples were obtained from E13 XX and XY pooled gonads. Approximately 20ng of total RNA from each sample was used to generate biotin-labelled cDNA. Approximately 2.5ug biotin labelled cDNA of each sample was used for each Mouse Genome 430v2.0 GeneChip array (Affymetrix). Significantly differentially expressed transcripts were identified using R/maanova. Statistical significance was determined at a false discovery rate value of equal to or less than 1%.