Net Terminal Genes (originally Net-tanmatsu-idenshi (ネット端末遺伝子?)) - These are the special genes which allow those possessing them full access to the Netsphere. However, the Net Terminal Genes are incredibly rare by the time period where BLAME! begins. The Net Sphere protection agency, also called the Safeguard, is under standing orders to kill any human found who does not possess these genes; also, any illegal access to the Netsphere is responded to by downloading a Safeguard to the location of the illegal access point and having it kill the person who attempted access. As very few humans in BLAME! possess the Net Terminal Gene, the Safeguards are essentially under orders to kill all humans (a goal that is shared by the enigmatic Silicon Life).