A) Febit miRNA arrays show 96.1% (296/308) of miRNAs encoded on all chromosomes except the Y were predominantly down regulated in GCKO testes by P18, with a small remainder (12/308 = 3.9%) upregulated. B) Validation of Febit miRNA array fold changes by qRT-PCR and primers amplifying miR-34b-3p, -15b-5p, -19a and -191. In comparison to WT (n = 3; RFC = 1.0), significant reductions in GCKO miRNA expression were observed using qRT-PCR and P18 RNA from GCKO testes (n = 3). C) Affymetrix ST 1.0 gene arrays showed dysregulation of 36.7% (7700/20985) of gene expression in GCKO testes with 55.7% (4290/7700) showing increased and 44.3% (3410/7700) showing decreased expression for autosomal genes. In contrast, X- and Y-linked genes were preferentially overexpressed in P18 GCKO testis samples (44.3% and 77.8%, respectively). D) Validation of Affymetrix mRNA array fold changes by qRT-PCR and primers amplifying genes highly expressed in somatic (Sox9) and germ cells (Stra8, Adad1, Bcl2l11, Kitl), and linked to X (Vsig4, Pgrmc1, Lamp2) and Y (Ube1Y1) chromosomes.