My double first cousins have Marfan's Syndrome.
The Mystery of Akhenaten: Genetics or Aesthetics?
Marfan's Syndrome: The most recently suggested possibility for Akhenaten's supposed pathology is a genetic disorder known as Marfan's Syndrome. This is a more likely possibility than Froehlich's Syndrome, as it does not affect intelligence or fertility (Burridge, A., 1995), (Redford, D., 1994).
I’ve got some double cousins, but no double first cousins, all good so far. :’) I wouldn’t mind being pharaoh, btw. ;’)