TRAF6 activates the NF-κB pathway while TRAF4 activates the MAPK pathway through degradation of the inhibitory protein DAZAP2 (deleted in azoospermia DAZ-associated protein 2) by Smad ubiquitin regulatory factor 2 (SMURF-2) (30, 87, 91, 92). The gene discussed is SMURF2; the disease is Azoospermia.