At GDC 2013, Kojima Productions showed off their new engine, and how it can capture real life persons and objects into the game relatively easily using 3D scanning. One of the doctors in the beginning of the trailer giving ECM to Snake is actually a scan of one of KP’s staff members, character modeling artist Mike Fudge.
On the screen in this photo you can see the character model standing in the meeting room. Kojima wrote:
At the beginning of “MGS5” trailer, there’s a doctor giving ECM to Snake. In fact this character was modeled by one of our staff, the character modeling artist, Mr. MIKE FUDGE. We did 3D captured of him w/i our studio and he polished himself.
Here is the character in the trailer:
This is one of the techniques the studio can ow use to speed up game development with the new engine.
Source: Hideo Kojima Twitter