STAC3 and Azoospermia: From the transcriptomic profiles of 4 normozoospermia and 27 non-obstructive azoospermia deposited in the GEO database (GSE45885), the expression levels of the STAC3 transcripts, were observed to be significantly downregulated in non-obstructive azoospermia compared to those in normozoospermia (P < 0.0001, Fig. 1a).