Well, there hasn't been a lot of research on it for obvious reasons, but I remember reading that the genetic mutation passed down in Blutbaden was caused by a viral infection.
خب زیاد رو این چیزا تحقیق نشده دلایل زیادی هم هست اما من یجایی خوندم اون جهش ژنتیکی که توی بلوتبادها رخ میده