CAIRO (REUTERS).- Ancient Egypt's teenage king Tutankhamun was born of an incestuous marriage, scientists said on Wednesday, helping to explain why he limped on a club foot and suffered other deformities and genetic defects.

Research including tests on the pharaoh's mummy, discovered in 1922 in the Valley of Kings, showed that his parents had been siblings and he had only paternal grandparents.

Incestuous alliances were common among Egypt's royalty, said renowned Egyptologist Zahi Hawass. "A king could marry his sister and his daughter because he is a god, like Iris and Osiris, and this was a habit only among kings and queens," Hawass told a news conference at Cairo's Egyptian Museum.

There has long been speculation about the fate of the king, who died sometime around 1324 BC, probably aged 19.

The scientists were presenting more details of DNA tests and CT scans conducted on Tutankhamun and 15 other mummies between 2007 and 2009. On Tuesday, they revealed that he had had malaria, a cleft palate and a genetic bone disease.

"This 21st century medical science allows for a more exact reconstruction of history," Albert Zink, a German member of the research team, told Reuters.

Scientists have identified Akhenaten, the "heretic" king who introduced monotheism to ancient Egypt, as Tutankhamun's father.

Akhenaten first married Nefertiti, who was renowned for her great beauty, but had no sons so he then married his sister in an effort to have a son.

Hawass said it would take several months to reveal more details about the identity of the Tutankhamun's mother.

Scientists are also looking for the mummy of queen Nefertiti but they have identified Ankhsenamun as Tutankhamun's wife. Two fetuses found in Tutankhamun's tomb, which was full of treasure, were identified as his offspring.

Depictions of Akhenaten with a bizarre feminine physique were due to the belief that god represented by the pharaoh was androgynous. "The artists used a poem Akhenaton wrote to god saying 'you are the man ... you are the woman' as a model for depicting fertility and the source of life," Hawass said.

He ruled out speculation that Tutankhamun and his father suffered from "Marfan syndrome" and another condition that could have led to enlarged breasts.

(Writing by Marwa Awad; editing by David Stamp)