Comparative gene expression profiling analysis of germ cell and stem cell markers. (A, B) Representative expression pattern of genes associated with germline development and meiotic commitment (A) or pluripotency (B) in mouse ESCs, embryonic PGCs, adult ovary-derived OSCs (freshly isolated and cultured) and juvenile testis-derived SSCs. Adult tail-snip fibroblasts (Fibrob.) were used as a negative control for specificity of pluripotency and germline gene expression, whereas β-actin mRNA was used as a sample loading control (no RT, PCR analysis of RNA sample without reverse transcription used as a negative control for excluding genomic DNA contamination).