Gabolde and Aidan Dodson claim that Nefertiti was indeed Tutankhamun's mother. In this interpretation of the DNA results, the genetic closeness is not due to a brother-sister pairing but the result of three generations of first-cousin marriage, making Nefertiti a first cousin of Akhenaten. The validity and reliability of the genetic data from mummified remains has been questioned due to possible degradation due to decay. When Tutankhaten became king, he married Ankhesenpaaten, one of Akhenaten's daughters, who later changed her name to Ankhesenamun. They had two daughters, neither of whom survived infancy. While only an incomplete genetic profile was obtained from the two mummified foetuses, it was enough to confirm that Tutankhamun was their father. Likewise, only partial data for the two female mummies from KV21 has been obtained so far. KV21A has been suggested as the mother of the foetuses but the data is not statistically significant enough to allow her to be securely identified as Ankhesenamun. Computed tomography studies published in 2011 revealed that one daughter was born prematurely at 5–6 months of pregnancy and the other at full-term, 9 months. Tutankhamun's death marked the end of the royal line of the 18th Dynasty. Reign Tutankhamun was between eight and nine years of age when he ascended the throne and became pharaoh, taking the throne name Nebkheperure. He reigned for about nine years. During Tutankhamun's reign the position of Vizier had been split between Upper and Lower Egypt. The principal vizier for Upper Egypt was Usermontu. Another figure named Pentju was also vizier but it is unclear of which lands. It is not entirely known if Ay, Tutankhamun's successor, actually held this position. A gold foil fragment from KV58 seems to indicate, but not certainly, that Ay was referred to as a Priest of Maat along with an epithet of "vizier, doer of maat." The epithet does not fit the usual description used by the regular vizier but might indicate an informal title. It might be that Ay used the title of vizier in an unprecedented manner. An Egyptian priest named Manetho wrote a comprehensive history of ancient Egypt where he refers to a king named Orus, who ruled for 36 years and had a daughter named Acencheres who reigned twelve years and her brother Rathotis who ruled for only nine years. The Amarna rulers are central in the list but which name corresponds with which historic figure