ASOIAF: If Melisandre's age is around 400, are there any theories to suggest that she played a part in the Doom of Valyria?

I've only heard reports that Carice Van Houten has said that she was 400 years old, and although it's based on something she has been told, I don't believe that GRRM would have been that specific.

However, there has long been a theory that Melisandre's true identity is a Melony Seastar, daughter of Shiera Seastar and Bloodraven(Brynden Rivers), both Targaryen bastards(and half-siblings who got it on....ah, yes, A Song of Ice and Fire.

This theory goes that she was born to Shiera Seastar(who refused to marry Bloodraven, preferring to incite his jealousy with other men) sold into slavery where she eventually made her way to Asshai to learn the way of Shadowbinding and become a Priestess of R'hllor.

The slavery bit is supported by the books(and the show, too, I believe) where she remembers being sold, under the name of Melony.

But the rest of it is pure conjecture based on a couple of things:

1. She's older than she looks.
2. She's magic, like Bloodraven.
3. Shiera was rumored also to have partaken in magical arts, bathing in human blood to keep her youthful beauty. (In-world conjecture.)
4. Her physical description shares things in common with Shiera Seastars: heart-shaped face, slim of waist, full breasts.

If this theory is true then Melly would be less than 400 years--perhaps closer to a hundred.

That's really the only theory that I've across regarding Melisandre. The theory goes on to posit that, having been born to slavery, she may be all unknowing of her heritage.

Personally, I do not think that Melisandre's heritage is all that important, though.

Written May 6th 2016