There's an entry in some terminal or a dialog or something that explains it? Same goes to Vault-Tec. And if they have researched and developed it before the war, why wait for 2178 and behave like FEV is discovered only now?

I'm told that Dr. Merrick is one of the brightest minds in the field of accelerated evolution, and apparently Vault-Tec agrees, because they've set up this Vault around him to suit all of his needs in the event that the bombs fall. All of his data and his work have been transferred to this facility from many important sources such as Mariposa Base West-Tek and Vault-Tec Labs I like Dr. Merrick. He's driven without being careless. He knows that in the event of a nuclear war, he may be the only person left in the world that can advance human genetics beyond where they are now. He's meticulous, detail-oriented, and reports everything to me on a regular basis.