Much of what is known about GBS is theory. The syndrome was thought to of been created when Tutankhamun was force fed the potion and beamed with the radiation of Aten. His children are thought to have had the syndrome but unlike their father they were not adversely affected by the syndrome and in fact actually benefitted from it. (More info on children) The same goes for all future ancestors but the syndromes benefits have been slowly diminishing with each iteration.
Aten's Blood
Aten's Blood is thought to literally be the blood of Akhenaten. Many theories that Akhenaten was mostly normal till he was blasted with the Heavenly Radiation of Aten. This energy made Akhenaten go through a spiritual metamorphosis and is most likely why he formed the religion Atenism. He then saved his blood which didn't decay and was sometimes called immortal blood. Only his close family was given this blood but only Tutankhamun was severely affected by it. It turned him into a monster with vast delusions. It is assumed in anger he reverted Egypt's religion back to the Old Kingdom religion. For Tuts blasphemy Aten Cultists used The Radiation of Aten on Tutankhamun, and from that day on he went from being Tutankhaten to the common name Tutankhamun. If modern Aten Cultists are correct Tutankhamun was born mostly normal but was deformed for his blasphemy.
Heavenly Radiation of Aten
Aten is assumed to be the solar disc or The Sun. Atenists say the Heavenly Radiation of Aten was channeled by a scepter and was absorbed in the brain or the abdomen or possibly both. It is thought that Tutankhamun was the last heir of Akhenaten to be blessed with the Heavenly Radiation. It isn't known why he rejected the gift of Aten, but it is thought that due to his struggle the beam caused severe damage to his brain and body. Also, one theory I have is that due to Tutankhamun being the son of Akhenaten Tutankhamun may have had an overdose on the Radiation of Aten. Atenists have said both of Tutankhamun's children survived and also had none of the issues that there father had. These children then had children and their ancestors are still alive today.
Cult of Aten
The Cult of Aten was thought to be formed in the 14th century BC by Akhenaten and was the Kingdoms religion for 20 years. Unlike the old kingdom religion Atenists worshipped only one God, Aten. Once Tutankhaten took the throne, he changed his name to Tutankhamun, but some Atenists say he was forced to change his name due to his blasphemy. It's a theme that if history says one thing the Atenists will have a different interpretation. Atenists take responsibility for the deformity of Tutankhamun when he rejected his father's gifts. Once Tutankhamun made it clear his ambition to revert back to the Old Kingdom Religion his children were hidden and switched out for two still Born's. The two children were raised in secret by Aten Cultists who hoped they would eventually bring the Egyptian people back to the light of Aten. This unfortunately didn't happen when Horemheb took the throne he struck Akhenaten's dynasty from the record and persecuted the Atenists and destroyed their temples. Some of the Atenists formed new religions and others survived underground. Many Atenist artifacts were lost in the purges which included the vials of Akhenaten's divine blood and the Holy Scepter of Aten. Without these artifacts it is theorized that the light of Aten will eventually go out since the only ones with Aten's Blood left are the heirs of Tutankhamun's two children.
The most documented and first person to have GBS was Tutankhamun. It should be known that this syndrome is only written about by Atenists and is just the individual symptoms to modern science and medicine. GBS seems to only effect those who are heirs of Tutankhamun and is becoming more and more prevalent the more diluted the bloodline becomes. Modern Medicine calls the first symptom Temporal lobe epilepsy and the second Paranoid Schizophrenia. Many Atenists believe that Temporal lobe epilepsy and paranoid schizophrenia didn't exist till after Tutankhamun was bathed in The Heavenly Radiation of Aten. GBS seemed to disappear for centuries after Tutankhamun. Almost all of the heirs of the Akhenaten dynasty viewed GBS as a boon that aided them with superhuman abilities and the ability to perform miracles. It seems starting in the medieval period some heirs started to get the negative effects of GBS. Atenists theorize that that the negative effects of GBS surfaced due to two factors, The diluting of the bloodline and the abandonment of Aten. Many Atenist hope and pray that the Scepter of Aten and the Blood of Akhenaten is found so the bloodlines divine energy can be restored.