The Silken Windhounds have some kind of greying gene.
It means that they will start to grey out in the face pretty early, some as early as 15 months.

And no, as far as I am aware, this is not yet something we can DNA-test for but that would not mean a difference, even it there was a test.

It is very simple, every single Silken Windhound has this gene. All of them!

Most will mainly grey out in the face. But some will also turn grey on more or less all of their bodies.

It is more common for Silkens to primarily grey out on the head.

Depending on the color of the Silken Windhound, it can be more or less difficult to actually see that there is any greying go on at all.

The ones that are the least affected are the black and tans.
They grey out later, or rather, it is their tan points that start to go white rather than grey. But it happens years later than when it usually starts for Silkens of other colors.