IPA-inferred top networks associated to Cluster A and B gene datasets. A) Top gene network generated by IPA for Cluster A down-regulated gene dataset. The network is centered around the key node gene BRCA1, involved in testis cell death. B) Top gene network generated by IPA for Cluster B up-regulated gene dataset. The central node of this network is SMAD3, involved in SCs functionality. Grey genes represent the deregulated genes associated to each Cluster while white genes represent those transcripts not modulated in KS testis vs. control testis.