User blog comment:Jack Pistol/Immortal Dovahkiin?/@comment-3194582-20121003151108/@comment-2040576-20121003160642

I am not sure if that is entirely true... The Septim bloodline had Dovahkiins, but I don't think that necessarily means that all Dragonborns are from the Septim bloodline. Unless some racial inter-breeding took place, there would be no explanation for the Dragonborns of a different race.