ITGA6 and Azoospermia: Pramod et al. identified the SSC subset of spermatogonial cells in Japanese Quail by immunostaining the testicular cells with the DAZL (deleted in azoospermia-like), ITGA6 (integrin alpha-6) and GFRα1 (GDNF family receptor alpha-1) molecular markers, which are routinely used for SSC identification in mammals [44].