Hutan Ashrafian, a British surgeon believes it could explain the reason behind King Tut's death in his teens - a question that has baffled historians for decades.
Ashrafian, from Imperial College London, points out that Tutankhamun and his immediate predecessors all died young and all had distinctly feminine physiques, the 'Daily Mail' reported.
Smenkhkare, a pharaoh who is believed to have been Tutankhamun's uncle or older brother, and Akhenaten, thought to have been his father, are depicted in paintings and sculptures with wide hips and large breasts.
Ashrafian points out that each pharaoh died at a slightly younger age than his predecessor, suggesting an inherited disorder.
This theory is backed up by the fact that the two pharaohs who came before Akhenaten - Amenhotep III and Tuthmosis IV - also appear to have had similar physiques.
King Tut's stunning tomb was discovered in 1922, sparking considerable debate over the cause of his young death.
Theories have included murder, a snake bite, leprosy, malaria, tuberculosis, sickle-cell anemia and even a chariot accident.
Ashrafian believes the pharaohs suffered from a heritable form of temporal lobe epilepsy, which as well as accounting for their abnormally large breasts would also explain why two reportedly experienced religious visions.
The condition is known to cause hallucinations particularly after exposure to sunlight.
And the temporal lobe is also connected to parts of the brain involved in the release of hormones involved in sexual development, explaining the development of large breasts.
Examination of Tutankhamun's mummified body showed he had a fractured leg which Ashrafian believes could have been the result of an epileptic seizure.
Tutankhamun, revered as a 'living god', was one of the most famous of a glittering dynasty who ruled over one of the world's greatest civilisations.