identification of TGCT genes involved in initiation and maintenance of transformed germ cells.. Mus musculus

Initially, we had compared gene expression differences in the embryonic gonads (E13.5) of the 129 and M19 strains by performing microarray analysis. These studies allowed us to identify downregulation of expression of the D19Bwg1357e, Zfp162 and Cox15 genes in the M19 strain. We next decided to examine gene expression profile changes in the embryonic gonads of 129 and M19 at additional stages so as to identify other TGCT genes from M19 that are also involved in initiation and maintenance of transformed germ cells. For this we isolated E13.5, E15.5 and E17.5 genital ridges from male embryos. Overall design: Microarray analysis of E13.5, E15.5 and E17.5 genital ridges from male embryos of M19 and 129. Total RNA prepared from the embryonic gonads were analyzed on 12 Affymetrix mouse 430_2 arrays. The objective of the analysis is to determine the differentially expressed genes for the following comparisons: 1. Comparisons of the two strains at each stage, specifically: 1a. 129-E13-GR vs. M19-E13-GR 1b. 129-E15-GR vs. M19-E15-GR 1c. 129-E17-GR vs. M19-E17-GR 2. Comparisons of the different stage in strain 129, specifically: 2a. 129-E13-GR vs. 129-E15-GR 2b. 129-E15-GR vs. 129-E17-GR 3. Comparisons of the different stage in strain CSS, specifically: 3a. M19-E13-GR vs. M19-E15-GR 3b. M19-E15-GR vs. M19-E17-GR After data process and quality assessment, 38069 out of 45101 probe sets proceeded for further analysis to identify differentially expressed genes. Hierarchical cluster analysis shows that samples of two strains from the same stage were grouped together and separated from the other stages (Fig.8). The initial analysis indicates a number of trends in gene expression patterns. Moreover, downregulation of expression of D19Bwg1357e, Zfp162 and Cox15 genes in M19 was also verified in this analysis. These data are currently being analyzed with the help of Dr. Y. Ji and L. Xiao from the Department of Bioinformatics and Computational Biology and Department of Biostatistics at M.D. Anderson Cancer Center. The results are unpublished.