Board Thread:TV Show Discussion/@comment-5014364-20160411185612/@comment-5014364-20160412160153

Grey Wolf Project wrote: If some speculation is right, and Tyrion is a Targaryen, would he be immune to Dragon Fire? And if so that would prove he’s Targaryen.

Immunity to fire wouldn't prove Tyrion is a Targaryen.

HOWEVER, what is seen as a test of Targaryen blood is if the dragons are friendly to you, and don't attack you on sight.

This was just a theory of course, even in Westeros. The Targaryens generally thought that you had to be descended from the blood of old Valyria like they were to bond with dragons -- though of course, MANY potential Targaryen dragonriders ended up being burned to death trying to take one as a mount (dragons are fickle).

It generally seems to hold true, and we saw a lot of this in The Dance of the Dragons when they had more dragons than riders and started recruiting Targaryen bastards to try to bond with the unclaimed ones.

The Targaryens recently intermarried with House Baratheon - Robert and Stannis's paternal grandmother was a younger Targaryen princess (in the novels, in the TV show this may have just been changed to their mother). Thus Stannis and Shireen have/had Targaryen blood.

More importantly now, it means that Gendry has some Targaryen blood, with a great-grandmother/grandmother who was a Targaryen.

Two of Robert's other bastards survived in the novels: Edric Storm (his only acknowledged bastard) now removed to safety in the Free Cities, and Mya Stone (living in the Vale, actually serving Sansa). Both were cut from the TV show.

House Martell also has some Targaryen blood though they intermarried much earlier, about one century ago (the marriage-alliance that brought Dorne into the realm). Within the novels, Martell characters speculate if their small bit of Targaryen ancestry might let them bond with Daenerys's spare two dragons. Doran's middle child Quentyn (totally cut from the TV show) directly tries this but ends up getting burned to death. Others might be more lucky.

So in the TV version, "potential dragon riders" we know of already include:
 * Gendry
 * The 8 Sand Snakes
 * Trystane Martell (and Doran, though he's an ill elderly man).