(I) In the process of Fas-FasL signal transduction, FADD, Daxx, FILP, and other related proteins are recruited by intracellular terminal DD; (II) after TNFR1-TNF binding, THE TNFR1 DD is induced to aggregate and recruit the bridging protein TRADD, which can recruit signal molecules such as TRAF2, RIP and FADD; (III) TRAILR1/2-TRAIL binds to FADD in cancer cells via DD. The gene discussed is TNFRSF1A; the disease is cancer.