Snapping pivot on vertex


I can move a mesh pivot using ALT+MMB+Drag (and not only MMB+Drag as
said in Doc). Ok.

But I would like to snap it to one of my mesh’s vertex.

I thought ALT+V+MMB+Drag would do the job. It would
have been logical because holding V key usually help with snapping
(…) but → not (too simple, maybe).

Is it possible ?

And if so, how ?

Thanck beforehand,

Sorry, UNREAL 4 is a very nice software, but somethings
seem so “unlogical” and hard to understand and/or
anticipate for me ! It makes me a little bit nervous …